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USING LAmRA'IORY EXPERIENCES WITH JGJRNAL WRITING
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presented by
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USING LABORATORY EXPERIENCES WITH JOURNAL WRITING
To TEACH A NUTRITIONAL UNIT
To 7‘" GRADE STUDENTS

By

Heather Ann Bradway

A THESIS

Submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree Of

MASTER OF SCIENCE

Division of Science and Mathematics Education

2000

ABSTRACT

USING LABORATORY EXPERIENCES WITH JOURNAL WRITING
TO TEACH A NUTRITION UNIT TO 7TH GRADE STUDENTS

By
Heather Ann Bradway

This project was designed to study the effectiveness of
innovative instructional materials created for a middle school health
science classroom. Students were provided the opportunity to learn
about nutritional concepts using constructivist methods. The goals
of this unit were that students would: 1.) recognize the different
nutrient components of food; 2.) establish the relationship between
good nutrition and a healthy body; 3.) interpret food labels using
their nutritional understanding; and 4.) construct their own
knowledge about nutrition through laboratory experiences. The
amount of understanding about nutrition between two classes Of
students was compared. In one class, laboratory activities with
traditional lectures were employed. The other class constructed
knowledge by using journal writings in conjunction with the
laboratory investigations. Students engaged in both writing and lab
experiences demonstrated a higher level Of understanding of the
concepts taught in the unit as indicated by pre and post test score

comparison and in the journal reflection and response questions.

ACKNOWLEDGMENTS

Many people have helped me complete this masters thesis,
none more than my husband Derek. Thank you for your gift of
encouragement and sacrifice. YOU reminded me one day three
years ago to believe in my abilities and now look at what that has
accomplished.

I would also like tO thank the Division Of Science and
Mathematics Education at Michigan State University, specifically Dr.
Merle Heidemann, for all Of her invaluable advisory support. Thanks
also to Dr. Ken Nadler, Dr. Marty Hetherington, and Dr. Howard
Hagerman who provided many rich and valuable learning
experiences at MSU. I also must thank Becky Murthum and Kathy
Dimoff who helped me with numerous arrangements in completing
the Frontiers seminars. Helen Waldo, is awesome because she can
make anything happen. Thank you to the Towsley Foundation for
the generous monetary support throughout my learning at Michigan
State University.

Finally, it is with much affection that I thank my colleagues
and friends who supported my efforts to complete this study. Thank
you Amy, Lisa, Deb, Joe, and Stella. You were like a family to me

while I was in East Lansing during these past three summers.

TABLE OF CONTENTS

LIST OF TABLES ........................................................................ vi
LIST OF FIGURES ..................................................................... vii
INTRODUCTION
I. Rationale for Study. ...................................................... 1
ll. Changing the Nature of My laboratory Instruction ............ 2
III. Maximizing the Learning Potential Of Laboratory
Experiences .................................................................. 5
IV. Demographics ............................................................. 12
V. Scientific Background .................................................. 13

IMPLEMENTATION OF THE UNIT

I. Overview. ................................................................... 20
II. Basic Outline .............................................................. 25
Ill. Unit Objectives ........................................................... 26
IV. Evaluation Protocols ................................................... 27
V. Laboratory Investigations: Description and Analysis ...... 29
EVALUATION
I. Pre and Post Tests ...................................................... 49
II. New Teaching Strategies ............................................. 52
III. Student Evaluation ...................................................... 55
DISCUSSION
I. What was Effective ...................................................... 58
ll. Changing the teaching of other units ............................ 61

Ill. Aspects of the unit that need improvement .................... 62

IV. Conclusions ................................................................ 64
LITERATURE CITED ................................................................. 66
APPENDICES

A. Resources ................................................................... 68

B. Pre and Post Tests ....................................................... 71

1. Nutrition Test Partl ................ I ............................. 72
2. Nutrition Test Part II ............................................ 75
3. Nutrition Test Part III ........................................... 76
C. Labs and Activities ...................................................... 77
1. Which Nutrients Do Foods Contain? ...................... 78
2. Vitamin C — DO You See It? .................................. 82
3 LactaidTM to the Rescue! ...................................... 89
4. Are Nutrients Found in What YOU Drink? ................ 92
5. Specific Gravity Investigation ................................ 97
6. Whose Urine Is It? ............................................... 98
7. Which Drink is the Most Nutritious? ..................... 104
8. Calorimetry Demonstration ................................. 106
9. Better Cheddar® Label Analysis .......................... 110
D. Student Survey .......................................................... 112
E. UCRHIS Approval ...................................................... 115

Table 1.

Table 2.

Table 3.

Table 4.

Table 5.

LIST OF TABLES

Pre and Post Test Data for Class A ............................... 49

Pre and Post Test Data for Class B ............................... 51

ttest Results Comparing the Means Of Three
Sets of Pre Tests from Classes A and B ................ 52

ttest Results Comparing the Means Of Three
Sets Of Post Tests from Classes A and B .............. 54

Student Evaluations Of Teaching Activities .................... 56

vi

LIST OF FIGURES

Figure 1. A Graph Comparing the Pre Test Averages Of Tests
I, II, and Ill Between Classes A and B .......................... 53

Figure 2. A Graph Comparing the Post Test Averages Of Tests
I, II, and III Between Classes A and B .......................... 54

vii

INTRODUCTION

l. Rationale for Study

As a middle schOOl science teacher, I am challenged
primarily in two ways. The first challenge comes from my students.
I need to maintain their interest, help them develop their critical
thinking skills, and encourage them to ask questions about the world
around them. The second challenge comes from myself, in striving
tO understand more about a given content area and also in
developing more efficient ways to help my students master a
particular concept. Being Offered the Opportunity to instruct a nine-
week health course for seventh graders gave me the chance tO
develop a unit with which I hoped to meet and exceed these
challenges from my students and for myself.

Within the arena Of health education, I chose to develop a unit
on nutrition. I found the subject Of nutrition boring and monotonous
because Of my prior experiences Of memorizing the functions of
vitamins and minerals and doing meaningless calculations with food
labels. I knew that if I could find ways Of making nutrition
interesting to me, I could make learning about nutrition fun for my
students.

A nine-week health course with a unit on nutrition taught four
times throughout the school year to different groups Of students can

lend itself to scientific study. TO develop new teaching strategies,

and then implement, adapt, and assess these strategies over time
could be accomplished with a course which was repeated throughout
a school year more easily than a unit which was taught only once
during the year.

Another reason for this study was to prove to myself the
validity of constructivist learning through the use Of laboratory
investigations. I had been introduced to this method Of teaching
during my undergraduate studies. However, it had not been until
after five years Of teaching and the course work at Michigan State
University that I could implement this teaching method with any
degree Of confidence. I had read about constructivism; now it was
time to put constructivist methods to the test.

The learning goals Of this unit were that students would:

1.) recognize the different nutrient components Of food;

2.) establish the relationship between good nutrition and a healthy
body; 3.) interpret food labels using their nutritional understanding;
and 4.) construct their own knowledge about nutrition through
laboratory experiences.

II. Changing the Nature Of My Laboratory Instruction

In my previous five years Of teaching, the textbook led the
direction Of my teaching, and subsequently, the learning
experiences of my students. I used laboratory activities. However,

it was apparent that my students were not connecting what was

happening during the activity to what was being discussed in class,
i.e., students did not understand the purpose behind the laboratory
activities. Additionally, I was concerned because students rarely
asked if they could experiment on their own. I wanted my students
tO engage in the activities with curiosity and take an active part in
what they were trying to discover with a sense Of personal
satisfaction.

My Old strategy of using laboratory investigations was similar
tO following a carefully laid out recipe. Students were given a
lengthy introduction. Next, they made a mad dash to complete the
cookbook style activity before the end Of the period. Following this,
students were expected to write a lab report with five distinct
secfions.

Within this lab report, students wrote out the “introduction”
section and the procedural section which was termed “method and
materials”. Both Of these sections could be copied easily from the
information provided in the lab handout. Students had tO design a
table or graph, which comprised the “results” section. This section
depicted the data that students had collected from the laboratory
activity. Additionally, in the lab report, students had to answer
questions in a “discussion” section. Finally, they wrote a brief
statement summarizing what they learned from the laboratory

activity in the “conclusion” section. I now see that there are flaws

with this layout. The following paragraphs describe my observations
regarding this method Of laboratory instruction.

When completing a lab activity in this manner, I had no way of
determining the prior knowledge Of a student. Also, much of the
writing was more like following a structured plan, the lab report,
rather than a means to explore and understand the relationships
between given ideas.

Since I also felt a sense Of urgency tO cover as many concepts
as I could to ensure that my students were getting the “best”
education, many activities ended up being rushed. This was
especially true during my first two Of years Of teaching. I would
push my students and myself tO complete the laboratory activity
within one fifty-minute class period, all so that I could move on to
the next section Of the textbook. Bob Tierney (1996) wrote that the
average high school text introduces seven to ten new concepts per
page and it was determined that a teacher wishing to cover an entire
textbook must introduce a new concept every two minutes. Applying
this statement to what I did in the past would imply that very few Of
my students had the necessary time to process the given laboratory
exercise and incorporate it into their schema Of understanding.
Rushing through laboratory activities without knowing the prior
knowledge of my students and to proceed through content believing

that more was better did not provide my students with the best

learning opportunities. Students may have felt frustration in trying
to connect what they understood to what they were experiencing in
class.

Endeavoring to be the best educator that I could be, it had
become apparent that I needed tO learn the constructivist approach
in teaching laboratory activities. Rather than directing my students’
learning, I chose to develop my abilities to guide student
construction Of understanding nutritional science. If students are to
achieve constructivist learning, I must employ constructivist
teaching (Appleton 1997). According to Patricia StOhr-Hunt (1996),
my role as a teacher must change from a knowledge giver tO one
which will allow students to construct their own knowledge through
meaningful experiences.

The rest Of this section is my interpretation Of this teaching
method, and how it can be used to enhance learning during
laboratory work and investigations.

lll. Maximizing the Learning Potential of Laboratory
Expefiences

When employing laboratory exercises as a means to facilitate
student understanding of a concept, the teacher must be careful not
to simply present a laboratory situation and expect students tO gain
from it what the teacher desires. Constructivism is more than .

leaving the student to “discover” the truth because many times a

student will formulate an understanding but not the one that a
teacher had intended (Driver 1983). It is important to consider that
everyone constructs meaning from an experience. However, the
meaning is based on earlier formed beliefs (Rutherford and Ahlgren
1990). This is when a misconception can be formed and sustained if
a teacher does not know what students believe to be true. A
misconception or alternative framework can interfere with the
understanding Of a student regarding a specific science activity and
can have a wider range of implications for understanding science in
general (Driver 1983).

Given that my old style Of laboratory investigations did not
make use Of identifying student misconceptions, the first change I
made was to include pre-lab activities which involved reflection
questions. My intentions with these questions were two-fold. The
first was tO determine where my students’ understandings were with
a given concept. Effective teaching begins with knowing students’
viewpoints about a concept (Pope and Gilbert 1983). Once I knew
what my students knew and believed about a particular idea, I could
use their current level Of understanding to increase their knowledge
about science concepts. This could be accomplished by creating
experiences which were meaningful and lead to further student
reflection and the formation Of new theories about nutritional

science (Ward, et al. 1996; Pope and Gilbert 1983).

The second function Of the reflection questions was to
generate student motivation through curiosity and conflict. I was
purposefully creating a level of cognitive appeal. Cognitive appeal
is directly related to differing levels Of curiosity, everything from
sensory experiences to discrepant situations or events (Martinez
and Haertel 1991). If students become curious about how
something affects the body, or why a particular solution changes
color, they will want to discover the “how” or “why” using
experimentation. This is especially the case when the questions are
crafted in relation tO their own life experiences with food and
nutrition. Also, if a particular question created Opposing ideas in
the minds Of students, it was my intention that the lab exercise
became a way for students to seek an answer (Rutherford and
Ahlgren 1990). Purposeful learning requires purposeful teaching
with specific learning Objectives on the part Of the instructor:
“Everything that a person does is shaped by intentions and learning
events must be seen as intentional” (Wheatley, 1991, p. 13). Also
with the introduction Of purposeful conflicts created by reflection-
based writings, students are forced to examine their misconceptions
and hopefully reorganize their ideas about the world (Wheatley
1991).

Early On in my study, I required students to keep a folder,

which contained all Of their lab reports, written responses to

questions, and tests. I soon found out that this was not a reliable
means to maintain student data. For accurate documentation of
data, I found that having students record their lab reflection
questions and subsequent lab analysis questions in a notebook,
which was termed a “Health Journal”, a much better choice.
Additionally, the notebook served as a tool of assessment and as a
catalyst for the construction Of student knowledge (Pierce 1998).
The notebook served as a point of discussion, both in pre and post
laboratory investigations. This discussion was necessary for
students to construct new knowledge (Tamir 1989). Having my
students write so much more was a major change from my usual
style Of instruction. Previously, all classroom activities had
incorporated writing as a tOOl to show that learning had occurred
such as the writing Of a traditional lab report following the
completion of a laboratory investigation. The constructivist model
challenged me to use writing as a tool for student learning (Ogens
1996). This type Of writing allowed my students to make predictions
about outcomes, and to construct new knowledge through a hands-
on experience about food and nutrition. Writing, whether reflective
or in application, provides students with the process to look back on
what they know, integrate old with new ideas, and to ask further

questions about what they now understand with classroom dialogue

either with peers or with the teacher (Fellows 1994). Simply put,
writing allows students tO think (Ogens 1996).

Ultimately, my goal was to use laboratory exercises as the
center Of my students’ construction Of knowledge instead Of lecture
notes. Many Of the books and journals that I read were helpful in
demonstrating the usefulness of the constructivist model. However,
I needed a practical example of how to turn my laboratory activities
into the necessary link between what students knew and the
intended learning outcome. In the article, “Linking Learning to
Labs”, by Wendy Pierce in the January 1998, Science m, a
template for creating laboratory activities based on constructivist
learning was modeled. Pierce wrote Of using reflective writing,
simple guidelines during the actual laboratory activity, student
discussions of what they Observed, some direct teaching, and finally
a set of application and analysis questions tO be answered by the
student. I used this basic model in the work described in this paper.

Another change that l incorporated was in the conclusion
statement typically found at the end of my students’ lab reports.
Bob Tierney (1996) had his students write a conclusion with the
following items in mind: 1) the best response to the original
question; 2) a reason for the response; and 3) any questions that
remain regarding the activity. I had my students write a conclusion

using the criteria described above instead Of simply addressing the

question, “What did you learn by completing the laboratory
investigation?”.

This format was different from what I had been using. I had to
rewrite, and in some ways simplify, all Of the labs that I originally
thought were adequate. I developed reflective writing sections in
the students laboratory investigations. Leonard Rivard (1994) wrote
that reflective writing is a tOOl for restructuring knowledge. I wanted
my students to examine what they understood and to reevaluate
what they believed to be true about a concept. If this was to occur,
questions needed to be designed which would allow for deeper
connections between prior knowledge and what students were
Observing during an experiment.

I also simplified the laboratory activities. Since my intention
was to have students complete the laboratory activity before any
formal instruction on a topic, I needed to shorten and clarify the
necessary protocols in the investigations. I did not want my
students to become frustrated with calculations, with unfamiliar
chemical equations, or a complicated list of instructions. Instead, I
wanted tO give them the liberty to explore and to form connections
with the newly presented ideas without being hindered by processes
which were not relevant to their learning of concepts Of nutrition

(Pierce 1998).

10

Students start to actively engage in the material when they
become involved in developing an experiment Of their own (Emery
1996). Having students do this would be a big change from my
previous attempts to implement labs and earlier trials Of this
nutrition unit! The focus changed from students simply finishing the
lab, to having the laboratory activity become a personal experience
in constructing knowledge about food.

All Of the previously discussed methods are in line with the
constructivist model Of using hands-on activities including laboratory
investigations to improve student learning and teacher instruction.
As Emery (1996, p.18) wrote:

The constructivist approach allows students tO “construct”

ideas and develop concepts one step at a time. Students

discover their misconceptions and, through a hands-on
approach, replace those misconceptions with truths. It is this
rebuilding Of their mental pictures and framework Of concepts
that keeps students so engaged in learning that they forget to
be uninterested in the subject.

I want my science class to be one where students become
curious, ask questions and are willing to search for the answers.
Science should be a process which allows students to gain new
information (Rutherford and Ahlgren 1990). With the implementation
Of this unit, a shift in my instruction has occurred. Of course, it may
take a while before I become completely comfortable with this

method of teaching. However, I believe that my students and I will

reap the rewards Of using the laboratory while creating personal

11

experiences through constructivist learning and this work provides
data that supports this belief.
IV. Demographics

I teach in a rural district in which the closest city has a
population of about seven thousand. The district is approximately
ninety miles from a city with a population greater than twenty
thousand. There are roughly 1,000 students, Of which over 98
percent are Caucasian. The middle school has approximately two
hundred and eighty total students in grades six, seven, and eight.
This study is based on a nutrition unit which I designed for a health
science class. The class is for seventh grade students and it falls
into the exploratory, or as we call it, “encore”, category since it is
nine weeks long as compared to eighteen weeks for a semester
course. Students rotate throughout the year, every nine weeks, with
a new encore class. Students have three encore classes a day in
addition to their four core (math, geography, science, and language
arts) classes. I taught the health class four times throughout the
school year for fifty minutes a day, which can make laboratory
activities difficult to run. Of the forty-five students split among two
classes who participated in this study, thirty were male and fifteen
were female. Forty-four were Caucasian and one was Of African-
American descent. Two Of my students were receiving services from

the special education department.

12

V. Scientific Background

Understanding human nutrition begins with knowing the
difference between the term nutrient and nutrition. A nutrient is
anything which the body needs to grow and is necessary for the life
processes. Nutrition is the scientific study Of how food affects the
overall health of the body. One may be confused with the difference
between food and nutrients. However, it is the quantity Of nutrients
within the food that makes it nutritious. There are six categories Of
molecules that compose the nutrients, including carbohydrates, fats,
proteins, vitamins, minerals, and water. The first nutrients discussed
in class were carbohydrates, commonly known as sugars.

There are two types of carbohydrates. Some are termed
complex and some are termed simple. Complex carbohydrates are
composed Of long chains Of glucose as well as other
monosaccharides bonded together to form a polysaccharide.
Examples of complex carbohydrates include starches and plant
fibers. Simple carbohydrates are composed Of one or two sugar
molecules. These monosaccharides include glucose, galactose, and
fructose. The other simple carbohydrates called disaccharides are
composed Of two monosaccharides bonded together to form the
sugars such as sucrose, maltose, and lactose.

The primary function Of carbohydrates in the body is tO serve

as a source of energy. When the body uses various enzymes to

13

digest sugars, all are converted into the monosaccharide, glucose,
also known as blood sugar. Interestingly, the most popular food
additive in the United States is sucrose. According to Jane Brody
(1988), people in 1988 consumed an average of 128 pounds Of
sugar each in a single year as compared with Americans a hundred
years prior who ate about forty pounds per year. Consuming too
much carbohydrate can lead to problems such as Obesity,
hypoglycemia, and hyperglycemia.

The next nutrient explored in this unit was protein. Proteins
are macromolecules, Often composed Of between one hundred and
five hundred amino acids in length. Of the twenty amino acids, eight
are termed essential. This means that the human body cannot
manufacture them internally, and it must find an external source
through the foods consumed. Proteins can come from both plant
and animal sources. The functions of proteins in the body are
numerous. They do everything from building tissue and replacing
cells to performing specific enzymatic reactions within the body.
Protein can also be used as a source Of energy for the body
however, carbohydrates are more efficiently converted for this
purpose. Eating too much protein can lead to kidney damage, losing
calcium, and increasing body fat.

In this unit, the necessity of fats was explored as well as the

problems associated with a high fat diet. Fats can be divided into

14

two types: saturated and unsaturated. Saturated fats contain all Of
the hydrogen atoms that fat molecules can possible hold. Saturated
fats are solid at room temperature. Unsaturated fats contain some
double bonds between the adjacent carbon atoms and do not hold
as many hydrogen atoms as saturated fats. Unsaturated fats are a
liquid at room temperature and are generally considered to be Oil.
Fats do not simply move about the bloodstream. They must be
prepackaged within an envelope called a lipoprotein. A high-density
lipoprotein or HDL contains more protein than fat and is then “less
sticky” in the artery than its counterpart, the LDL or low density
lipoprotein. Conversely, a LDL contains more fat than protein and is
more sticky in the bloodstream. TOO much fat in a diet can cause
problems beyond the expected Obesity. If the majority Of a person’s
diet consists of foods high in saturated fats, high levels Of LDL in
the blOOd can result. In addition to increased LDL, high levels Of
cholesterol, a molecule found only in animal fats, can increase the
chances Of developing atherosclerosis. This starts a domino effect
which can lead tO high blood pressure and tO a heart attack or
stroke. Fats do serve a useful purpose in the body. They act as an
insulator under the skin and as adipose tissue surrounding organs.
Additionally, fats are necessary for hormone production as well as

for the absorption Of the fat-soluble vitamins, A, D, E, and K.

15

Another pair Of nutrients discussed was vitamins and minerals.
Vitamins are complex, organic molecules which help in various
chemical reactions throughout the body. Vitamins are divided into
two categories based on solubility. They can be either fat-soluble,
such as the vitamins A, D, E, and K mentioned earlier, or they can
be water-soluble. A few commonly known water-soluble vitamins
include vitamin C, the B complex vitamins, and biotin. Minerals are
inorganic but also perform a wide range Of vital functions in the
body. Minerals are considered tO be macro or micro in nature
depending on how much is required by the human body. The best
way tO get the daily requirement of essential minerals and vitamin is
through the foods eaten. Various diseases and complications can
result if the proper amounts of each are not consumed.

The final and most vital nutrient is water since the body can
only survive three to five days without it. People should drink at
least six 8 ounce size glasses Of water daily. Even if someone does
not directly consume this amount Of water, they can Obtain it from
the ingested foods. One such example is green beans, as they
contain eighty-nine percent water.

After developing an understanding Of what nutrients are and
how they differ from food, one can explore how nutrients influence
the nutritional value Of a food. The greater the variety Of nutrients

found within a food, the more nutritious the food. This is especially

16

true if the food has not been processed or refined and is low in
calories. Of course, more of a nutrient is not always better, as is
the case with the presence Of sodium or saturated fats.

In addition to nutrients and nutrition, the concept Of energy or
calories stored within some Of these nutrients should not be ignored.
There are differing amounts Of calories in the various nutrients and
foods. The term calorie is defined as the amount Of heat required to
raise the temperature of one gram Of water one degree Celsius.
This energy can be measured from food by using a device called a
calorimeter. This device allows a given amount of food to be
burned. A given amount Of water is situated above the burning food
item. As the food is burned, the heat generated raises the
temperature Of the water. It is possible to calculate the amount of
energy released as calories as a result of burning the given amount
of food. Both carbohydrates and proteins release fOUr kilocalories
or 4000 calories with every gram burned. Fat releases nine
kilocalories per gram burned. Understanding the relationship
between nutrients, food, and caloric value is important in being able
to decipher food labels and deciding which foods to consume on a
daily basis.

Being able to make informed decisions about which foods to
eat is important; however, another nutritional concern is

understanding the relationship between the types Of nutrients

17

consumed and their effect on a person’s health. One such cause
and effect relationship is adult-onset diabetes mellitus and the
presence Of glucose and ketones in the urine.

Type II diabetes or adult onset diabetes results from an
absence or inactivity Of insulin in the blood. Insulin, a protein
released from the pancreas, helps glucose enter cells throughout
the body. A problem with insulin can lead to excess or high blood
sugar which can be measured in the urine. Excess glucose is
converted into fat. Fat can clog arteries, leading to high blood
pressure and to heart problems. Other problems resulting from
complications with type II diabetes include kidney damage, retinal
damage, skin and urinary infection, and ketosis. Ketosis occurs
when fats are used for energy instead Of carbohydrates. When a
person has type II diabetes, the body is unable to use glucose and
the excess ketones, which are measurable in urine, can make the
blood acidic and poison the brain.

Adults can get this type Of diabetes from years of poor eating
habits, including the over consumption Of foods containing refined
sugar and flour. In addition, a lack Of regular exercise can
contribute tO the inactivity of insulin. Heredity also plays an
important part in the development Of this disease which kills at least

one thousand Americans every day.

18

There are many diseases that can be studied in order to
understand the connections between nutritional choices and health.
Type II diabetes serves as an easy model to examine for this
purpose. A complete list of the resources I used in gathering this
scientific information and designing the activities can be found in

Appendix A.

19

IMPLEMENTATION OF THE UNIT

I. Overview

Since I have taught this unit four times during the period Of the
past year’s research, the method of delivery evolved as I
implemented more Of the constructivist style in teaching laboratory
activities. At the beginning Of the school year, during the initial
implementation Of this unit, I used a student survey and a series Of
pretests as a means to identify student misconceptions. In later
iterations, I made use Of student journals in addition to the survey
and the pretests. I found that l was better able tO facilitate a
laboratory experience if students had questions in mind and a sense
Of personal purpose before attempting the lab. This was done by
incorporating a series of reflection questions prior to doing the
laboratory activity. These questions required students to write and
think over what they knew about the given topic. Students would
then embark on a mission of investigation instead Of simply doing
what I tOld them to do in order to get a good grade (Smith 1990).

For purposes of completing this study, two classes Of students
were compared. The first class studied came from the second
iteration and was termed, “A”. With this class I implemented the
newly developed laboratory activities. The second class studied

was termed, “B” and came from the third iteration. The students in

20

Class B were provided with constructivist learning Opportunities in
addition to the laboratory activities.

Students in group B were provided with a spiral bound
notebook at the beginning Of the unit. Within the notebook, termed
the “Health Journal,” the reflection questions were answered in
complete sentences. It involved some extra work for me; however,
it was absolutely necessary that I review the answers to the
reflection questions prior to the completion Of the labs. Questions
were not graded for content but only for effort and completeness of
thought

In addition to engaging the student as observed in their
journals, the reflection questions provided a means to identify
student misconceptions, allowing for the appropriate adjustments Of
a given laboratory activity. After spending a class period writing
and discussing reflection questions with peers and me, the students
would engage in the laboratory investigations.

All Of the laboratory exercises were developed as a result of
my coursework and research at Michigan State University (Summer
1999). Each activity was designed with the intention of engaging
students and helping them develop a deeper level Of understanding
Of various nutritional concepts. Additionally, students in group B
were given no lecture notes prior to the labs. My purpose in

omitting lecture notes was to facilitate student understanding as a

21

result Of the experience with the lab rather than through direct
instruction using lecture notes.

TO complete the laboratory exercises, students would work
in groups Of two tO four. Students were required to record all results
in the form Of tables or charts within their journals. The time taken
to complete laboratory investigations was not an issue. If three
class periods were needed tO do the lab then three periods were
used.

Once the lab was completed, the students and I would discuss
the results. This was done because, in many instances, different
student groups did different parts Of the investigation, and the class
needed the data to Obtain the “big picture”. Students were also
encouraged to share their insights about what they had learned as a
result Of completing the lab. Additionally, class discussions were
used tO explain any chemical processes or terms which may have
caused confusion. Students were instructed to wait until after the
class discussion tO complete the next section Of the laboratory
experience, which included the journal response questions and the
statement Of conclusion.

The final stage Of the laboratory experience consisted Of two
parts. The first was journal response questions tO be written in the
health journal Of each student. The purpose Of these questions was

to determine student understanding at the application and synthesis

22

levels. During the second part, students were required tO write a
statement Of conclusion regarding the laboratory investigation.
Within the conclusion, students were to express the answer to the
question provided at the beginning Of the laboratory activity (Often
found in the title Of the activity), and then to explain why they
formed a given answer. The responses written by students were
graded for content and their ability tO explain answers, citing
examples from the lab experiences. Journal response questions
and the conclusion statements were graded immediately following
the laboratory investigation.

Additionally, students were to write any questions about the
activities that were still unanswered. This provided an added
assessment regarding the success Of the laboratory design. The
structure Of the laboratory activities can be condensed as:

1). reflection; 2). action; 3). results; 4). direct teaching; 5). journal
response writing; and 6). conclusion statement.

After the entire laboratory experience was completed, I
provided remaining critical information in the form Of notes on the
given concept to the students. Following the notes, the students
once again began a series Of reflection questions for the next lab
and the entire process would continue. After a series of laboratory
investigations and notes, with each lab focusing on no more than

two to three concepts, tests were given to measure student learning.

23

Three sets Of pre and post tests were administered (Appendix
B). The first pre and post test focused on carbohydrates, proteins,
and fats. The second tests focused on water, vitamins, and
minerals, in addition to additives and preservatives. The final set Of
pre and post tests assessed student understanding Of calories and
the effects Of nutrition on the health of individuals.

Many new teaching techniques were developed as a result Of
my research project. They can be summarized as: 1.) journal
writing; 2.) reflection questions and a defined conclusion statement
within the laboratory write-up; 3.) increased student discussion prior
to completion Of the lab; 4.) completion Of labs prior tO lecture; and

5.) increased time for completing learning activities.

24

II. Basic Outline

This unit on nutrition required five weeks Of instructional time.
All of the activities are new and are the result Of my coursework and
research at Michigan State University (Summer 1999). A complete
copy Of each laboratory investigation and activity can be found in
Appendix C. The numbers in parenthesis after each activity
represent the Objectives addressed, which can be found on the
following page.

A. NUTRIENTS FOUND WITHIN FOOD
Carbohydrates and Proteins (1, 2, 4)
Sugars in Cereals (3)
Vitamin C in Juices(1, 3, 4, 5)
Lactose in Milk (1, 4, 5, 8)
Using a Hydrometer in Liquids (4, 5)

Fats, Proteins, and Carbohydrates in Liquids
(1, 2, 3, 4, 5)

@9995)?”

B. DISEASES, NUTRITIONAL CHOICES, AND HEALTH
1. Glucose, Ketone, and Protein Determination Through
Urinalysis (1, 3, 4, 5, 7)

C. CALORIES AND THE NUTRITIONAL VALUE OF FOOD
1. Nutritional Label Analysis Of Various Drinks (3, 5)
2. Calorimetry Demonstration (6, 7)
3. Food Label Analysis (3, 6, 7)

D. ASSESSMENT
1. Journal Response Questions and Conclusion
Statement

2. Pre and Post Tests
3. Surveys

25

III. Unit Objectives

All of the following Objectives were taken from the Michigan
Essential Goals and Objectives for Science Education (MEGOSE).
These Objectives consist Of constructing, reflecting, and using
scientific knowledge tO implement instruction and tO assess student
learning. The New Directions teaching unit called FOOd, Energy and
M, which was produced by the State Of Michigan (1992), also

helped tO organize my nutrition unit in terms Of Objectives.

1. Generate scientific questions about the world based on
Observation.

2. Design and conduct simple investigations.
3. Use sources Of information to help solve problems.

4. Write and follow procedures in the form Of step-by-step
instructions, recipes, formulas, flow diagrams, and sketches.

5. Evaluate the strengths and weaknesses Of claims, arguments, or
data.

6. Explain how cells use food as a source Of energy.

7. Compare and contrast food, energy, and environmental needs of
selected organisms.

8. Explain how cells use food to grow.

26

IV. Evaluation Protocols

In determining the overall effectiveness of this unit there were
three levels Of assessment. The first level was the pre and post test
scores for those forty-five students who participated in this study.
There were three separate pre and post tests throughout the unit
(Appendix B). They consisted entirely Of constructed response
questions, since it was important that student understanding could
be accurately assessed. Nothing could be left to chance as would
be the case in a multiple-choice style test where students can
guess.

The second level Of assessment was the journal response
questions and the conclusion statements. The written response
questions were designed tO measure the effectiveness Of the
laboratory experience in terms Of implementation and increased
student understanding. The conclusion statement required each
student to write about any further questions that she or he had
regarding the laboratory activity.

In evaluating the individual activities I examined the journal
work Of six students, two high-achieving, two average, and two low-
achieving students from Class B. The achievement level was based
on their first semester standings in their “core” classes (math,
geography, science and language arts). The high achieving

students both earned all A’s in the first semester, the average

27

students earned a combination Of B’s, and 0’3, and the low
achieving students earned D’s. It was necessary to rate
achievement in this manner since Health science is an “encore”
class, and I do not have these seventh grade students in the core
science classes. I have these seventh grade students for a period
Of nine weeks before the next rotation Of encore classes begins.

TO evaluate student attitudes on the different laboratory
activities and on the different modes Of implementation, I conducted
surveys Of all students in classes A and B before and after the unit’s

implementation. This survey can be found in Appendix D.

28

V. Laboratory Investigations: Description and Analysis
Appendix location Of each activity is in parenthesis.
Activity: Which Nutrients DO Foods Contain? (C1)

The purpose of the first laboratory investigation was to have
students Observe the presence Of various nutrients within food.
These were proteins, simple carbohydrates (glucose), and complex
carbohydrates (starch). Students used Biurets reagent to indicate
the presence of protein, glucose strips for glucose, and Lugols
solution for starch. Some Of the foods tested were in solution while
other samples remained as they would be found in a grocery store.
The journal response questions were designed so that students
would have to think about which nutrients might be found within a
given food item. The student responses to these questions revealed
a single misconception. Three Of the six target students were
confused about the definition Of a nutrient. They wrote that
nutrients found in foods included items such as caffeine and wheat.
All six students appeared to understand that it was possible for a
fOOd tO contain more than one nutrient since they had read nutrition
facts or labels on cereal boxes or on a milk cartons. While
completing the laboratory investigation, students were allowed to
choose five food items to test. If they brought an item from home,
they could test it for the various nutrients with my permission.

Students were broken into groups Of four, and each group was

29

assigned to test for a specific nutrient. Each group was also
responsible to test a “mystery food” for nutrient content. The use Of
an indicator seemed to generate interest and it appeared they were
familiar with its purpose. After completing the lab and filling in the
charts with the data that their group had collected, a class
discussion followed. Each group shared their results and we filled
in the entire chart for all Of the food items available. There was
some confusion as to a positive or negative result with a given
indicator. Color interpretations can be subjective for students
unfamiliar with the use Of indicators. I can tell them that a certain
color means positive or negative, but until they experience it for
themselves, they simply are unsure how to interpret the results Of
the indicator tests.

Their journal response questions revealed that learning had
occurred. Students demonstrated that they could name the nutrients
that comprised the foods they tested. Additionally, all six students
could explain the importance of using an indicator tO complete the
laboratory investigation. They were also able to infer that if a food
did not react positively for any nutrients that this did not necessarily
mean that it was void of any nutrients.

The problem Of color interpretation with the indicators used
became apparent on the post test results. Two Of the six students

wrote that foods like apples and onions were high in protein. All six

30

students were able to state that bread or cereal were foods that
were high in carbohydrates. Additionally they were all able to write
about how foods contain more than one nutrient with five Of the six
students using examples from their laboratory experience. The last
question on the test asked students how they would determine the
nutrient components Of a mystery liquid. Five Of the six were able to
describe an experiment using indicators to identify nutrients within
the mystery fOOd.
Demonstration — Sugars in Various Foods

The next demonstration-style activity was intended to generate
interest Of sugar content in prepared foods. Students were shown a
two-liter bottle Of Mountain Dew® pop. I tOOk out some granulated
sugar and asked them to guess how much sugar was equivalent to
the amount found in the two-liter bottle. This led tO some interesting
discussion; however, for the most part, students guessed low on the
amount Of sugar. They were very surprised when I showed them
that a two-liter Of Mountain Dew® contains sixty-eight teaspoons Of
sugar! Immediately after this demonstration, students were given a
copy Of a list from Jane Brody’s Nutrition Book, Of popular breakfast
cereals showing the percentage Of sugar found within one serving Of
the cereal. Students were then instructed to look up their favorite

cereals and find out what percentage was sugar. This activity

31

certainly generated interest and many students tOOk the list home to
show their parents.
Lab: Vitamin C — DO You See It? (CZ)

The next laboratory investigation was designed to allow
students to test for the presence Of vitamin C in various drinks
including orange juice, Mountain Dew®, Powerade®, Sunny Delighte,
and the juice from a pepper. The Objective of the lab was two-fold.
The first was to give students the opportunity tO determine
nutritional value of the drinks they consume in terms Of vitamin C.
The second was tO find out whether or not the preparation Of a drink
affected its vitamin C content. Out of all Of the laboratory
investigations modified, this one was changed the most. The
original lab included calculations tO determine exactly how much
vitamin C was within a given sample. The calculations involved
basic algebra. However, after implementing this lab a couple Of
times, I found that students did not have the prerequisite math
skills. I dropped the calculations starting with the third iteration Of
this activity.

One of the reflection questions asked students to rank the
above mentioned drinks in terms Of highest to lowest in vitamin C
content. The reflection questions indicated that advertising has
influenced what students think about the nutritional content of food.

Five of the six target students thought that fresh orange juice had

32

the most vitamin C and another wrote Sunny Delight® was highest.
In terms Of being the lowest in vitamin C content, four wrote that
Mountain DeW® would have the lowest, one wrote that “pepper juice”
was lowest, while the others did not answer that question. Another
reflection question asked if the way a food was prepared affects the
vitamin C content. Most students replied that vitamin C content
would lower with cooking, however all six students were unsure as
tO why this would occur.

Students were divided into groups Of four. Each group was
responsible to test six different juices three times for the presence
Of vitamin C. Students placed one milliliter Of the indicator solution,
indophenol, within each test tube. Students then carefully dropped
the sample juice or drink into the test tube until the indicator either
became clear or until its color no longer changed.

The journal reflection questions showed some inconsistencies
in the student results. Students were asked to determine which
drink had the highest vitamin C content. One student reported that
Sunny Delight® had the highest vitamin C content. I can only guess
that his group mislabeled their test tubes or that they did not swirl
the test tube after each additional drop of juice. Three Of the other
students wrote that boiled orange juice had the highest vitamin C as

it only took two drops Of the juice to change the indicator to a clear

color. The remaining two students did not answer this question.

33

All six students reported that bottled orange juice had less
vitamin C than fresh orange juice. They all wrote in their journals
that processing does affect the vitamin C content within a product.
What puzzles me is that when it came to the post test, two Of the six
were unable to respond positively to the question, “Does it matter
whether orange juice is fresh or bottled, when considering the
amount of vitamin C present? Why do you think 30?”. Perhaps
more class discussion was necessary since all of the students
clearly still did not have the cause and effect relationship solidified.
I could make the lab groups smaller using two students per group
instead of four, making sure that all Of the students have a hands-on
experience with the vitamin C laboratory investigation. I could also
split this lab into two separate activities in which one qualitatively
analyzed different beverages for vitamin C and the other activity
investigated storage and processing of drinks. With the later
activity, I could have student groups share and make sense Of the
separate data collected, allowing them to form ideas explaining
changes in vitamin C content.

In an “application” journal response question, students were
asked how they would ensure that they would consume the
recommended daily allowance (RDA) Of vitamin C. Three Of them
stated that they would consume orange juice, while another wrote

that she would take a vitamin supplement (we never discussed these

34

in class), and the last two students did not provide an answer. This
shows that it can be difficult for students to apply what they have
learned tO their own situation. I should provide more practice for my
students using further discussion and laboratory situations so that
they can correctly apply this information.

LAB - Lactaidm to the Rescue! (C3)

Since I am trying tO use examples Of food and nutrients from
popular culture, I developed a lab using a product like LactaidTM a
product which commonly has advertisements on television. The
purpose Of this lab was to give students an experience with the
terms “lactose intolerance” and to recognize that nutrients affect
people negatively. A secondary outcome Of this lab was that
students would understand that enzymes are required for the
digestion Of certain nutrients, and that temperature can affect the
ability Of an enzyme to work within the body. The pretest revealed
that about half Of all students knew that lactose was a type Of sugar
in milk. This seemed reasonable; students have probably heard the
terms “lactose intolerance” in television commercials for products
like LactaidT", or perhaps they may know someone who has a
problem digesting lactose. The reflection questions told me,
however, that even though some students know what lactose is, they
did not understand the connection between the specific nutrient

lactose and being lactose intolerant. Five out Of the six students

35

wrote that being lactose intolerant means that a person cannot
consume dairy products and wrote nothing Of being unable to digest
the sugar, lactose. All six students were able to characterize
enzymes as proteins. However, they could not explain their
funcflon.

During the laboratory investigation, students were given
samples Of milk, either at room temperature or refrigerated
temperature, each with either boiled lactase, unboiled lactase, and
no Iactase. Students were then given glucose strips to test for the
activity Of the enzyme, lactase which breaks down the disaccharide
lactose into the monosaccharides galactose and glucose. Students
Observed the effects Of temperature on the activity Of an enzyme by
measuring the content of glucose. More importantly, students
inferred the levels Of lactose within milk while using the glucose
strips.

After completing the activity, five out Of the six students stated
that they knew the LactaidT" worked because the glucose strip
changed in color; however, only one student wrote that this change
was the direct result Of lactose being digested by the enzyme
Iactase. All six students recognized that the inability to digest milk
sugar is called “lactose intolerance”.

When asked if anything in the lab sped up or slowed down the

activity of the enzyme, all six reported that temperature affected this

36

activity. They stated that the amount of glucose indicated by the
strips told them how much the enzyme worked. Four of the six
students wrote that heat sped up the activity, while the other two
stated that colder temperatures slowed the activity Of the enzyme.
Only two Of the students wrote anything about how boiling the
enzyme destroyed its ability to work. When asked to explain the
title Of the lab, four Of the six students were able to write about how
people who are lactose intolerant can use LactaidTM for digestion Of
dairy products.

After I analyzed this laboratory activity, it appeared that the
test questions needed tO be rewritten so that they clearly measured
the Objectives to be learned by the students during the activity. In
the case Of this laboratory and the test, only one question
addressed a concept discussed in the lab. More questions are
needed to accurately assess the learning and retention and Of
knowledge by students. A better question would have been, “Which
nutrient found in milk can affect people adversely? What is this
problem called and what can be done about it?”

LAB — Are Nutrients Found in What You Drink? (C4)

Students were given another Opportunity to use indicators on
different drinks and to determine the specific gravity Of each. The
purpose Of this laboratory exercise was to reinforce the idea that

various nutrients are found within foods by measuring the density

37

and that these nutrients affect the nutritional value Of a food. The
pretest showed that students were confused about the relationship
between being nutritious and having specific nutrients within a given
food item. Very few students were able to provide a specific
example Of how the presence Of a nutrient made a food nutritious.
Many simply wrote that a food is nutritious because is has nutrients
in it. There was no mention Of the types Of nutrients or the amounts
Of nutrients found in the fOOd. In a reflection question addressing
the same types Of issues, one student wrote that milk was the most
nutritious of all the drinks that he had consumed that day because it
contain over four hundred different types Of fats. The misconception
is that having more Of a particular type Of nutrient means that the
fOOd is more nutritious. Another misconception revealed by the
reflection questions was that water is the most nutritious drink. I
understood why so many students wrote this since I had tOld them
earlier that week that water was the most vital of all the nutrients
since humans could only live without it for about five days. The
students Obviously were confused about something being vital and
something being nutritious. TO clear up these terms before the lab,
we spent some time discussing what made a food nutritious. I
brought in instant rice, a turkey sandwich on wheat bread with
mayonnaise and lettuce, and a pop tart. This encouraged students

to speak about which food was more nutritious and why. I stressed

38

the idea that more Of a particular nutrient does not always mean that
it can make a food more nutritious.

While completing the lab, students worked in groups of four.
Each group was assigned a specific drink to test using the indicators
Biurets reagent and Lugols solution. Students also had to
characterize the density Of the drink by using a hydrometer. It was
apparent after reading the students’ pretests and reflection
questions that they had nO idea what a hydrometer was, how it
worked, or what it measured. Students were introduced to using a
hydrometer prior to completing the lab activity. A copy Of the
activity using a hydrometer can be seen in the Appendix (C5). The
hydrometer was something that students were fascinated with and
enjoyed using. Since they were familiar with the use of the various
indicators, this portion Of the lab went smoothly. In addition to
using indicators and a hydrometer, students were also required tO
read the food label of the drink they were investigating. This was
done partially to prepare them for the next series Of laboratory
investigations, but primarily to have them evaluate the nutritional
content Of the drink in relation to the nutrients for which it tested
positive.

As revealed by the journal response questions, students were
able to identify various nutrients within the drinks. They were also

able to make the connection between the nutrients found and the

39

nutritional value Of that drink. When asked if a soft drink was a
good source of nutrients, all six target students replied that it was a
poor choice. They said that the soft drink was full of sugar and that
it contained no proteins or vitamins. The next part Of that question
asked students whether a diet version Of the same soft drink would
be a better choice. Four students replied that it was a worse choice
than the regular soft drink. The other two students concluded that
being a diabetic was a good reason to consume the diet soda rather
than the regular soda.

The post test showed that students learned from this
laboratory experience. All six students cited milk as being the most
nutritious Of all of the liquids tested, which was my intention in this
laboratory exercise. Most students wrote that milk was the most
nutritious because it contained all Of the categories Of nutrients.
Only one wrote Of milk being nutritious because, it has fats that
our body needs.” This was the same student who wrote the
statement about milk being nutritious because Of all the different
fats it contained. The misconception that this student had about
what makes something nutritious did not change even after
completing two weeks Of activities. This example served as proof
that what a student believed to be true, otherwise termed as an
alternative framework, was indeed difficult to change even with

hands-on activities and personal experiences.

40

All six students also demonstrated on the post test the
understanding Of how a hydrometer worked. Their interest was
captured during this portion Of the laboratory experience, and many
included a drawing of the hydrometer in their post test. The
response question, “What could (specific gravity) indicate about the
nutritional value Of that liquid?” was a source Of confusion for
students. Four out Of the six students wrote that the higher specific
gravity readings indicated that the liquid was more nutritious. They
did not speculate that the density Of a liquid does not necessarily
correspond to the nutritional value Of the liquid. I do not blame the
students for being unable to make this connection. I should have
worded the question differently: “What is the relationship between a
quuid’s specific gravity and its nutritional value?” I need to spend
time developing activities which would allow students to understand
the difference between the chemical and physical characteristics Of
a food.

LAB - Whose Urine Is It? (C6)

Since students should have a grasp of what a nutrient is and
that nutrients are found in foods, the next step was to help them
determine the relationship between what was eaten and the health
Of an individual. The pretest indicated that students did not
understand how urine could provide clues to a person’s health. It

also indicated that they could not provide a specific example Of how

41

unbalanced nutrition affects a person’s health. Next I will describe
the urinalysis lab as well as student progress related to the lab.

Before students completed the lab, it was necessary tO have a
class discussion about the clues imbedded within each scenario
described in the laboratory handout. The lab begins with a fictitious
history of three patients and the possible compounds which may be
present in their urine samples. I discovered the first time after
implementing this exercise that students asked questions about the
significance Of patient behaviors like eating only grapefruit for a
month or urinating frequently coupled with a lack Of energy. They
also wondered about possible health consequences which could be
indicated in urine. l was reminded that seventh grade students lack
the physiological knowledge to make inferences about food choices
and possible health outcomes without teacher guidance.

The purpose Of this laboratory experience was for students
to test simulated urine for the presence Of compounds which could
indicate a health problem. This would in turn introduce them tO the
connection between food choices and diseases like diabetes. The
laboratory investigation involved a scenario in which three urine
samples were “mixed up”. It was the students’ job to read over the
patient histories, interpret the symptoms, and then to make a
prediction about the compounds which could be present in the

various urine samples. Students worked in pairs and were given a

42

beaker with an unknown urine sample. They then used urinalysis
strips to identify the compounds found in the urine. Based on the
results, students then indicated which urine sample they had and
why they thought so.

This was an easy lab to complete since it simply involved
dipping urinalysis strips into synthetic urine, and then interpreting
the results as indicated on the strip. The journal response
questions showed that only two Of the six students were able to
establish the connection between eating an unbalanced diet and
finding compounds in the urine that could possibly indicate the
presence Of a disease. I thought this was the case because there
was some confusion over the words “unbalanced and balanced
nutrition”. We did not complete any activities which would have
cleared up these terms for the students. Additionally, I should have
included a journal response question specific to the term glucose,
and how its presence in urine could be an indication Of diabetes.
Again I see the importance Of creating well written questions in
order to guide and assess student learning. The Ultimate goal Of
this lab was to allow students to make a connection between what
was eaten and how health was impacted, however the processes
involving metabolism are pretty complicated. The experience itself
was not enough to ensure conceptual change and integration of

knowledge by students.

43

In their conclusion statements, all six students were able to
support their choice Of which patient’s urine sample they possessed.
Students were able to base the results Of their urinalysis on the
clues provided in the patient histories. When asked what further
questions they had regarding this laboratory activity, three Of the
students replied that they wish they could have tested the other
urine samples since each group was allowed tO choose only one
sample. At least I know that they were curious. The other three
skipped that portion Of the question.

ACTIVITY — Which Drink is the Most Nutritious? (C7)

The next activity completed in class was one involving the
analysis Of the food labels Of three drinks: milk, orange juice, and
orange pop. The purpose was to evaluate a food based on the
content Of its fOOd label and applying nutritional knowledge tO a
situation. This activity was very similar tO what students had done
in the past with nutrients and how the proper amounts Of them can
make a fOOd more nutritious. Additionally, the label analysis
activity served as reinforcement for understanding and interpreting a
food label for nutritional content. I tried to remove the brand names
on each of the fOOd labels since numerous class discussions on the
topic Of drinks and nutrition had taken place and I wanted students
tO evaluate these liquids based on how they interpreted the fOOd

label. This assignment was a given as homework. Most students

44

chose milk as the most nutritious. However, the misconception that

“more is better” came up again. A few students wrote that milk was

more nutritious since it contained the most sodium. Certain trains Of

thought are difficult tO stop!

LAB - ls Energy Stored Within Food? A Calorimetry
Demonstration (C8)

By this point in the nutrition unit, students should understand
what a nutrient is, be able to determine whether one food is more
nutritious than another and be able to explain how fOOd choices can
positively or negatively impact health. The next step I wanted my
students to make was to understand the concept that energy stored
in food is measured in the form Of calories. One way to demonstrate
the idea of energy stored in food is to complete a brief study on
calorimetry. The purpose Of the calorimetry activity was to allow
students an opportunity to witness the stored energy (through
burning) in a food and then to calculate the amount Of energy stored
in that food. Another Objective of this activity was to apply
nutritional understanding to the idea that caloric amounts influence
the nutritional value Of a food.

Even though we had discussed the idea Of stored energy in
food, specifically that associated with certain nutrients, students still
could not explain why certain types Of fOOds provided more energy

than others. They were unable tO make the connection between

45

food, the nutrients they contained, and the amount Of energy stored.
Only one Of the six students in the reflection questions said that a
fatty food contained the most energy. The students were also
confused with the term “empty calories”. When asked what it meant,
four Of the six revealed that a fOOd containing empty calories was
one which did not have any calories. Either the students have not
connected nutritional value to the amount of calories within a food,
or they did not understand the terms used. A better reflection
question would have been, “Why can’t we survive well on only
chocolate bars?”.

During the demonstration, I used different students to help me
with the calorimetry of a Better Cheddar® cracker. I chose this food
because I knew that it would burn readily. The class then recorded
the data as the student helpers called it out, and we completed a
chart as a class. This part of the lab required a class period. The
next day the class discussed what they had seen and the concept of
calories. Following the discussion we completed the calculations tO
determine caloric content together. Finally, students were given
time to write their journal response entries.

The journal response questions indicated that all six students
understood that energy was stored in food because the food burned
and the temperature Of the water in the calorimeter increased. They

also demonstrated this point by writing the answer to the question,

46

“Are calories found within food?” as “yes” in their conclusion
statement by restating how they witnessed the food burning. The
misconception persisted that there was no connection between
caloric amounts and nutritional value Of a food. Only two Of the six
students were able to write that food contains calories and that
these calories come from proteins, fats, and carbohydrates. I
should have provided a calorimetry experience in which a variety Of
foods were tested instead Of only crackers. This may have provided
the students with more experience and more time to form the
necessary connections between nutritional value and the calories. I
also need tO be more active in reviewing student work in progress
and provide suggestions or further questions when it appears that
students are not making the intended connections.

On the positive side, the results Of the post test show
excellent progress with this portion of the nutrition unit as the class
average was slightly above eighty-five percent. l was pleased that
my students were able to demonstrate a mastery level Of
understanding with these concepts. I need to examine why so many
students were successful and provide the same types of
experiences consistently throughout my curriculum.

Activity - Better Cheddar® Label Analysis (CO)
The final activity Of the nutrition unit coincided with the

calorimetry demonstration. Students were provided with a copy Of

47

the nutritional label tO the Better Cheddar® crackers. The purpose
Of this activity was tO give students practice interpreting what was
on the label and determining the nutritional value of the food.

Students were given a short time to complete the worksheet in class

and a discussion followed.

48

EVALUATION
I. Pre and Post Tests (Appendix B)

The questions on the pre and post tests were written in short
answer format. They were designed to elicit student responses that
could demonstrate learning Of nutritional concepts at all levels of
Bloom’s taxonomy. I tested the students on three separate
occasions throughout the five weeks Of the unit generating three
sets Of pre and post tests. The two classes Of students involved in
this study were similar in academic stature, attitude, and interest in
nutrition. Students in both classes made significant gains over the
course Of the unit as measured by these instruments. The results

for the first class studied, “A”, are shown in Table 1.

Table 1. Pre and Post Test Data for Class A

 

 

 

 

 

 

 

n Mean Percent Standard Range
‘ (%) Deviation
Pre test I 24 6.9 23 3.85 1-14
Post test I 24 21.5 72 5.15 11-19
Pre test ll 24 1.8 9 2.37 0-10
Post test ll 24 13.6 68 4.20 8-12
Pretest Ill 25 1.2 8 1.10 0-3
Post test Ill 25 8.2 55 3.40 1-12

 

 

 

 

 

 

 

 

The implementation Of the nutrition unit in Class A involved my
traditional approach with lecture first and the newly created

49

laboratory exercises following. Students in this group demonstrated
an increase in knowledge about nutrition (Table 1). The class mean
increased by 14.6 points on the first pre to post test, an
improvement of forty-nine percent. The second test mean increased
by 11.8 points, with an increase Of fifty-nine percent, pre to post.
The third and final post test mean increased by 7 points over the pre
test, an increase of forty-seven percent. What is interesting with
Class A, is the gradual decrease in post test averages with each
test administered. The first post test’s average was seventy-two
percent. The second post test’s average was sixty-eight percent
and the third post test averaged a lowly fifty-five percent. I think
this is a direct result Of the types Of questions asked on the tests
and the activities which were taking place in the classroom. The
nutritional concepts which students were expected to learn became
increasingly geared toward deeper learning in the application,
evaluation, and synthesis levels Of understanding. The classroom
experiences of my students probably did not allow them to
understand the concepts at the level that they were being tested
since they had very little writing to learn experiences.

The implementation Of the nutritional unit in Class B involved
more Of a constructivist approach to teaching because it included
journal writings and class discussions. The mean score for all
three post tests was considerably higher than that of Class A. The
results for the second class, “B” are shown in Table 2.

50

Table 2. Pre and Post Test Data for Class B.

 

 

 

 

 

 

 

n Mean Percent Standard Range
(%) Deviation
Pre test | 19 6.9 23 3.95 0-12
Post test I 19 23.7 79 3.64 15.5-29.5
Pre test ll 20 2.2 12 1.78 0-6
Post test I! 20 15.5 78 3.22 9.5-20
Pre test Ill 19 1.5 10 1.31 0-4
Post test Ill 19 13.2 88 2.10 8-15

 

 

 

 

 

 

 

 

With the first set of pre and post tests, the mean score
increased by 16.8 points, an increase Of fifty-six percent. The
second post test showed an increase Of 13.3 points compared to the
pre test, an increase Of sixty-six percent. The final test showed an
increase Of 11.7 points pre to post, an increase Of seventy-eight
percent. The class averages in each Of the three post tests were
all above the highest score of Class A. Class B post test averages
were seventy-nine percent for the first post test, seventy-eight
percent on the second post test, and an incredible eighty-eight
percent on the final post test. The high success rate for Class B on
the third post test suggests a correlation between constructivist labs

with journal writing and the types Of questions found on the test.

51

II. New Teaching Strategies

Laboratory experiences appear to increase student learning as
seen in the pre and post test comparison for both classes Of
students. The next question that I had was whether the change in
unit implementation between Class A and Class B was statistically
significant. In order to compare the independent test means
between Class A and Class B, a series Of Student’s ttest was done.
The pre tests between both classes was compared statistically
(Table 3). This was needed to show that the post test gains were
actual and that both classes started at the same level Of
understanding. A graph comparing the pre test average
percentages between the two classes is shown in Figure 1.

Table 3. ttest Results Comparing the Means of Three Sets Of Pre
Tests from Classes A and B.

 

 

 

 

Data where Degrees t test Reject or
Ho: pt = [.12 and F °§ Accept Ho
(1 = _05 ree om (No difference
between pre test

scores)
Pre test IB — Pre test IA 41 .043 Accept
Pre test IIB -- Pre test ”A 42 _571 Accept
Pre test lIlB — Pre Test “IA 42 .792 Accept

 

 

 

 

 

 

The results (Table 3 and Figure 1) show that both classes

started out at the same level Of understanding Of nutrition. There

52

was no significant difference in the average of the pretest scores

between the first class studied and the second class.

Figure 1. A Graph Comparing the Pre Test Averages of Tests I, ll,
. and Ill Between Classes A and B.

 

 

 

 

 
 
   

Average
Percentage 10

 

I Pre tests

 

IA IB IIA IIB IIIA IIIB
Pre Test Number and Class

 

 

 

A second ttest comparing the independent means of the post
test scores from each class shows a statistically significant
difference in post test scores of Class B over Class A only for the
third test (Table 4 and Figure 2). Students in Class B scored seven
percent higher and ten percent higher than in Class A on the first
and second post tests respectively (Tables 1 and 2). Despite the
fact that the post test comparisons for tests one and two were not
statistically significant, I am convinced when I read the student
responses to test questions that there was a difference in student

understanding between the two groups.

53

Table 4. ttest Results Comparing the Means Of Three Sets of Post
Tests from Classes A and B.

 

Data where Degrees of t test Reject or
Ho: [11 = In and Freedom Accept Ho (No
a = _05 difference

between post
test scores)

 

 

 

Post test IB — Post Test IA 41 1_55 Accept
Post test IIB — Post test “A 42 1,72 Accept
Post test IIIB - Post test IIIB 42 5_65 Reject

 

 

 

 

 

 

Figure 2. A Graph Comparing the Post Test Averages of Tests I, II,
and Ill Between Classes A and B.

 

 

 

60

Average 50
Percentage 40
30

20

10

0

I Post tests

 

 

IA IB IIA IIB IIIA IIIB
Post Test Number and Class

 

 

 

In studying the answers given by students on the post tests
from the two classes, there was a difference in the depth of the
answers given. One example is the response to the question, “Why
is it important to know what nutrients are found within food?". Most
of the students in Class A wrote answers similar to the following
response, "It’s important to know what nutrients are found within a

54

food so you would know if it is healthy or not”. This leaves me
wondering what the student means by the term, “healthy”. In Class
B, the answers were more specific and showed signs Of making
connections with their prior knowledge. One such response to the
above question was, “It is important to know what nutrients are
found in foods so we can eat right, not have tOO much Of one thing,
and avoid things we’re allergic to”.

In another question, “Explain the following statement: Milk is
Nutritious”, a far greater percentage Of students from Class B were
able to respond with specific examples. One student wrote, “Milk is
nutritious because Of all the nutrients in it like calcium, protein,
vitamins, and carbohydrates.” A few students in class A responded
similarly to the students in Class B. However, over half Of Class A
lost points because they were unable to provide more than one
nutrient found in milk as the reason why it is nutritious. Both
classes completed the same lab activity, but Class B had the lab
experiences and the additional constructivist support both before
and after completing the laboratory activity.

Ill. Student Evaluation

Students were given a survey (Appendix D) which asked
questions about nutritional knowledge, laboratory investigation
preferences, and changes that could be made to the unit. These
students were asked to number each learning activity between one
and six, with one being the highest or most helpful and six being the

55

lowest or least helpful. Although both classes Of students were
given surveys to fill out, only in Class B were students asked to rate
which classroom activities helped them to learn the most. The

results from these questions are summarized in Table 5.

Table 5. Student Evaluations of Teaching Activities Used in
Class B.

 

Teaching Activity Effectiveness
Mean Score

 

 

 

 

 

Completing a Lab 3.06
Taking Notes 3.18
Watching a 3.41
Demonstration
Listening in Class 3.59
Discussion with 4.35

Classmates

 

Writing in a Journal 4.81

 

 

 

 

Students felt that laboratory activities were the most useful in
helping them to learn. The laboratory activities appear to motivate
students to learn. I was surprised to learn that students felt that
taking notes helps them to learn almost as much as completing a
lab. As I analyzed the survey results, I noticed that almost as many
students who rated a particular question a high rating of “one”,

almost an equal number rated the same question low “six”. In

56

general, the high mean scores for the results Of Table 5 may be a
result Of students not recognizing their own learning styles.

Another survey question asked which learning activity students
enjoyed the most. The highest number Of students replied that labs
were the most fun, with watching demonstrations next, followed by
classroom discussion, and finally listening in class. NO students
listed taking notes or writing in their journals as being the most
enjoyable learning activities. Both groups Of students were asked
which laboratory activity stuck out the most in their mind. Out of the
forty-six students responding, twenty-five wrote the “Urine lab”,
nineteen wrote the “Calorimetry lab”, and two wrote the “Milk lab”
otherwise known as, “Lactaidm to the Rescue!”

According to the survey, students felt that classroom
discussions and writing in their journals were the least helpful. I
found these responses interesting. What my students’ thought
about what helped them to learn was contrary to what my study
about constructivist teaching and learning demonstrated. There
appears tO be a positive correlation between what was learned and
the use Of writing in addition to laboratory experiences with Class B.
I can state this because Of the comparison between post tests and

the average increase in scores Of Class B over A.

57

DISCUSSION

I. What was Effective

Using laboratory experiences coupled with writing-tO-Iearn
activities proved to be the best way for students to construct
knowledge about some aspects of nutrition because in each of the
three tests, students in Class B scored higher than in Class A. If
students are tO achieve deeper levels Of understanding, it is not
enough to implement laboratory activities without providing the
Opportunity tO connect prior knowledge tO the new concept. The use
Of the “Health Journal” with the second class proved to be an
invaluable tOOl in achieving this goal. The reflection question
responses, which were required before each laboratory activity,
gave me a glimpse of what the students understood about a topic.
This was a technique that I had never employed in any of the
classes that I had taught. Not only did the reflection questions
serve me as an instructor, but they also served as a means for
creating curiosity and conflict about a concept for the student.
Instead Of solely trying to complete an activity and get a good
grade, students were starting to ask how they could change certain
variables within an experiment. One example of a question a
student asked after completing the reflection questions on a
particular lab was, “How much protein is in an ant?” I think that this

would make a great laboratory investigation and could lead into

58

some interesting discussions. Other students became actively
involved in the laboratory investigations and started to bring in their
favorite drinks and snacks to test for the presence Of different
nutrients. I rarely had students showing so much curiosity before
the use Of constructivist methods.

By allowing students to process the information in terms to
which they could relate, students should be able to construct
knowledge at a level which would allow them to apply it tO a
different situation. This was accomplished through student driven
discoveries by lab experiences and journal writings. Students were
able to demonstrate a deeper level Of understanding by their written
responses to purposeful questions whose answers were found within
the labs. One such example came after completing the lab called,
“Lactaidm to the Rescue” (Appendix C). In response to the
question, “How can our body temperature and the effects Of having a
high fever impact our health?” one student wrote, “I think our body
temperature and the bad effects Of having a very high fever impact
the many enzymes found in our bodies because heat destroys the
enzymes and they won’t work “. This student demonstrated how the
laboratory experience with the lactase and the heating Of it led to a
connection with understanding how enzymes work within people.

Another change shown to be effective was the revision Of the

conclusion statement students wrote after completing a laboratory

59

investigation. Before the implementation of the unit, I simply asked
students to summarize what they learned after doing the lab. This
type Of questioning is not specific enough to lead students to write
about the connections made between prior knowledge and the new
construction of knowledge. With the new conclusion statement, I
could determine whether students understood the purpose Of the
laboratory investigation. Additionally, I could also gain a sense Of
their reasoning abilities by the way they supported their answers.

As an instructor, I also appreciated the additional questions
about an investigation students posed following the completion Of a
lab. After completing “Are Nutrients Found in What You Drink?”,
one student wrote in their conclusion statement, “Nutrients are in
liquids. I know this because we tested different kinds Of liquids and
there were proteins and glucose and we looked at the back labels.
Some questions I have are ‘What’s so important about density?’ and
‘Is it good to have density?’”. From the statements that this student
made, I can tell that the purpose Of the lab was understood and the
logic used to support the answer was correct. Additionally, I was
able to determine that the portion Of the lab which pertained to the
hydrometer and to the density Of liquids needs to be clarified.

The conclusion statements written after completing “Whose
Urine Is It?”, indicate that students wished to test additional urine

samples. One student writes, “ In the lab I found out that I had

60

patient 1 because of what I found in his urine. I am wondering what
the other patients had and how much Of it they had in their urine.” I
will change this activity and allow students to test all urine samples.
This will allow students to become more confident about their
interpretation Of the test strips as each urine sample provided has
different compounds present. Another student writes, “The purpose
Of this laboratory investigation is to know about what can happen to
your body if you do not eat a balanced diet...DO we need ketones?” .
This conclusion statement indicates that I need to provide additional
learning activities which address the compounds found in urine as
well as what the presence Of these compounds may indicate about
the health Of an individual. In either case, the conclusion statement
provides the teacher with a snap shot Of the learning which has
occurred and indicates the changes that need to take place allowing
specific learning Objectives tO be accomplished.
ll. Changing the teaching of other units

The power Of reflective questioning has changed me as a
teacher. I plan to incorporate this teaching technique in all Of my
future laboratory investigations. I can also recognize the
importance Of including more writing-tO-learn activities in all Of the
classes I teach. I liked using the journals as a means of
assessment, and I plan to continue using them. The journals served

as a tOOl in following the thinking patterns Of students as they

61

changed over time. They also helped me find the flaws with the
questions I was using to measure student learning. The well
thought out question is invaluable with helping students to reach a
deeper level Of understanding.

Another change in teaching style which I plan tO implement
into other units, is to give students a laboratory experience before
the information has been given on the topic. This causes students
to engage in a topic with their own thoughts, allowing for true and
lasting changes in their understanding. Changes like these will take
time, since I will have to reorganize my teaching strategies. I am
confident, however, that my students will benefit and become better
thinkers after integrating this style Of instruction throughout my
curriculum.

Ill. Aspects Of the unit that need improvement

When comparing the test questions with the laboratory
activities completed, it was easy to understand why students in
Class B did much better on the second post test and very well on
the third post test. Over half Of the questions on the second test
were related to three laboratory activities which students had
completed. As the Class B average Of eighty-eight percent
indicated on the third test, every test question was directly linked to
the four activities which had taken place during class. Contrary to

the third test and second tests, the first test could use some

62

improvement. I need tO be better aware Of what my instructional
goals are and to have the test questions measure the desired
learning outcomes. Additionally, I need to create more lab
activities, particularly in the first section Of this unit. This is
especially true since students were asked a variety Of questions, yet
only one laboratory activity had taken place by this point in the unit.
Most Of the questions from the test were derived from the notes
rather than from the laboratory investigation.

Another change that I would make in this unit is tO encourage
additional higher level thinking within the journal response
questions. As I looked over these questions, very few of them
provided students with an opportunity to apply what they had
learned to a new situation. Students can only show what they
understand when given well thought out questions and laboratory
expeflences.

I also wonder about student attitudes. On the survey I should
have asked whether “encore” classes mean as much tO students as
“core” classes. If students feel that encore classes are not as
valuable, they may not work as hard as they could to understand the
concepts they are being introduced to during class. I bring up this
point because students indicated on the survey that writing in their
journals was the least useful in helping them tO learn. The truth is

writing is hard work because it forces a person to think. My study

63

shows that students learned more as a result of completing the
laboratory experiences in conjunction with the journal writings and
discussion. I had hoped that their attitudes would have reflected
their success.

Another interesting point of study would be to have given
these two groups the same set Of tests a month after completing the
unit. It would be informative to measure how much students retain
knowledge in comparison to the learning/teaching methods used
during class.

V. Conclusions

I can now understand why some Of the best learning occurs
when students are allowed to question, write, and investigate
through personal experience a challenging concept. I now
appreciate the constructivist model as a means to allow my students
the best chance for learning in the science classroom. Learning
occurs at a deeper level when students use laboratory experiences
coupled with journal reflection and response questions along with
classroom discussions. As a teacher I must be purposeful in
designing laboratory activities which will enable students to achieve
the learning outcomes desired. The power Of pre-lab activities like
the journal reflection questions should not be overlooked as they
can Open a teacher’s eyes tO the level Of knowledge that their

students have at any given time. This can allow a teacher to adjust

64

the learning/teaching strategy as needed by that particular group Of
students. The journal response questions need to be well thought
out and able to measure student understanding. They should guide
student thinking in the construction Of new knowledge. If a teacher
wants to find out if the purpose of the lab is understood, a specific
laboratory conclusion statement must be required from the students.
Finally, after the labs, journal responses, and discussions have
occurred, the test questions need to consistently reflect the
constructivist learning activities which have taken place.

I enjoyed this style of teaching as I found that there was less
student confusion surrounding the purpose Of the laboratory
investigations and students seemed to have a better grasp Of the
procedures. This new style Of teaching also increased the level Of
teacher responsibility, as I had the additional reading of journal
reflection questions before students could complete a lab. However,
it also increased the responsibility Of the student for his or her own
learning.

I am pleased with the student learning outcomes resulting from
the implementation of this unit on nutrition. I know that l have
become a better teacher and my students will benefit for years to

come.

65

LITERATURE CITED

Appleton, K. (1997). Analysis and Description Of Students’ Learning
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Driver, R. (1983). The Pupil As Scientist? Philadelphia, PA: The
Open University Press.

Emery, D. (1996). A Constructivist Cloud Lab. Science Scope, (pp.
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Fellows, N. J. (1994). A Window into Thinking: Using Student
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Martinez, M. E. & Haertel, E. (1991). Components Of Interesting
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Ogen, E. M. (1996). The Write Stuff. Science Scope, (pp. 15-17).

Pierce, W. (1998). Linking Learning to Labs. Science Scope, (pp.
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Pope, M. & Gilbert, J. (1983). Personal Experience and the
Construction Of Knowledge in Science. Science Education, 67, (2):
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Rivard, L. P. (1994). A Review of Writing to Learn in Science:
Implications for Practice and Research. Journal Of Research in
Science Teaching, v. 31, n. 9, pp. 969-983.

Rutherford, J. F., & Ahlgren, A. (1990). In Effective Learning and
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Smith, E. L. (1990). A Conceptual change Model Of Learning
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NJ: Lawrence Erlbaum.

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Tierney, B. (1996). Write to Learn Science. Arlington, VA:
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Ward, K. et al. (1996). Constructing Scientific Knowledge. The
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67

APPENDIX A

Resources

68

Anspaugh, David J. & Ezell, Gene. Teaching Today’s He_alth in
Middle and Secondary Schools. New York, NY: Macmillan College
Publishing CO., Inc., 1994.

Brody, Jane. Jane Brodv’s Ngtrition Look. Toronto, Canada:
Bantam Books, 1987.

Bullerwell, Lornie, Valerie Raunig, and William Hagar. “A Bio-
Engineered Enzyme”. The Science Teacher. January 1994.

“Does Cooking change Vitamin 0?”. Science Interactions
Laboratory Manual Teacher Edition. GlencoelMcGraw-Hill, 1994.

“Food, Energy and Growth”. New Directions Teachm Unit_s_.
Michig_an Science Education Resogrces Project. The State Of
Michigan, 1992.

 

Hechtlinger, Adelaide. Handbook Of Modern Experiments for High
School Biology. West Nyack, NY: Parker Publishing Company, Inc.,
1971.

Marieb, Elaine N. Human Anatomy and Physiology. Redwood City,
CA: The Benjamin/Cummings Publishing Company, Inc., 1992.

Mehas, Kay Y. & Rodgers, Sharon L. Food Science: The
Bigchemistry Of Food and Nutrition. New York, NY:
GlencoelMcGraw Hill, 1997.

Michigan State Board Of Education Michigan Essentijall Ggals and
Objectives for Science Education (K-12). Lansing, MI. Michigan
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MorhOlt, Evelyn., Brandwein, Paul F., & Joseph, Alexander. A
Sourcebook for the Biological Sciences. New York, NY: Harcourt,
Brace & World, Inc., 1966.

69

Schmude, Judy. “Clinical Urinalysis: Implications for Teaching”.
I_h_e American Biology Teacher. Vol. 43, NO. 3, March 1981.

Shmaefsky, Brian. “Artificial Urine for Laboratory Testing-
Revisited”. The American Biology Teacher. VOI. 57, NO. 7, October
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Shmaefsky, Brian. “How-TO-DO-lt Artificial Urine for Laboratory
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1990.

Zar, Jerrold H. Biostatistical Analysis. Englewood Cliffs, NJ:
Prentice Hall, Inc., 1984.

70

APPENDIX B

Pre and Post Tests

71

Nutrition Test Part I
Carbohydrates, Proteins, and Fats

Read the following questions carefully and answer the questions the
best that you can with as much information as possible.

1. Define the word : nutrient

2. Identify which of the four examples is not a nutrient and explain
your answer. A) Carbohydrates B) Water
C) Hormone D) Protein

3. What is the most popular food additive in the US?

4. Explain why natural sugars are more beneficial than refined
sugars?

5. What is “blood sugar”? (DO not write — “sugar that’s in the
blood”)

6. Name a food, which you think is nutritious, and explain your
answer.

7. How can excess sugar impact your health? (Give two
consequences)

72

8. LOOk at the diagrams below and choose the molecule that is a

sugan
A). B). C). O-q-O
H H H H IC'9 9
I l I I 9-0-0-0
-C — C - C — C - H \ C ’ O-O-O-O-O-O
I I I l ‘0 O
H H H "I {3.0

9. Explain why eating whole wheat bread is better than eating
white bread.

10. Name a food which is a good alternative to having sweets.

11. Which nutrients do fruits and vegetables contain? How do you
know?

12. Name a food that is rich in carbohydrates. How do you know?

13. What function do carbohydrates perform within the body?

14. Name a food that is rich in proteins? How many servings of
protein do you need a day to be healthy?

73

15.

16.

17.

18.

19.

20.

21.

22.

23.

What makes one food more nutritious than another?

What function (job) (10 proteins perform within the body?

How can too much protein damage your body?

Which type Of fat is a solid at room temperature?
Circle one: Saturated Unsaturated

Name the type of fat which has been shown to clog arteries?

Fats are necessary for good health. Explain.

True or False: A food can contain more than one nutrient.
How do you know?

Why is it important to know what nutrients are found within
food?

If you were given a mystery liquid and asked tO determine
which nutrients it contained, how would you determine this?

74

Nutrition Test Part II.
Milk, Water, Additives & Preservatives, Minerals, and Vitamins

1. Name the sugar that is found in Milk and the enzyme which is
needed to digest it. What is the term given to someone who
cannot digest this milk sugar?

2. Explain the following statement: Milk is nutritious.

3. Explain how the specific gravity demonstration showed how much
“stuff” is in a liquid? Which liquid had the highest amount Of
particles in it? What could this indicate about the nutritional level
of that liquid?

4. What is our most vital nutrient? Why do you think so?

5. What are FOOD ADDITIVES and provide an example?

6. Explain how vitamins are different from minerals?

7. Provide a specific example Of how nutrition affects our health:

8. True or False . A food like green pepper can contain more
vitamin C than fresh orange juice. Explain how you know.

9-10. Does it matter whether orange juice is fresh or bottled when
considering the amount of vitamin C present? Why do you
think so?

75

Nutrition Test Part III.
Calories and Effects of Nutrition on Health

. Which nutrients provide energy tO the body?

. Which nutrient holds the greatest amount Of energy per gram Of
that food type? How do you know?

. What is a Calorie?

. Look at the food label. Which nutrient provides the greatest
number of calories? What percent Of this food is fat? Show
your work.

. What device can be used to determine the amount of energy
found in a food sample? Explain how it works.

. Explain how urine can supply clues to show the health of
someone.

. Using what you have learned from this entire nutrition unit,
explain how nutrition can effect the body? Provide an example of
each situation.

a) Balanced nutrition:

b) Unbalanced (poor) nutrition:

76

APPENDIX C

Labs and Activities

77

1. Which Nutrients DO Foods Contain?
Purpose:

By using different nutrient indicators, you will be able to determine
which nutrients are found within various foods. Two Of these
indicators are for carbohydrates (one for sugar, and the other for
starch, both of which are carbohydrates), and the other test is for
proteins.

For all Of these tests, we will start with four very simple foods, and
then use a few more foods that you can bring from home. This will
allow you to test some Of your favorite foods.

Each lab group will be in charge of testing for a specific type Of
nutrient found in food. Be sure to record which test your group has
been assigned.

Materials:

-Safety goggles

-A grease pencil

-Several foods:
Corn starch dissolved in water
Glucose (sugar) dissolved in water
Gelatin dissolved in water
Mystery fOOd solution

-Other foods for testing such as:
banana, oatmeal, egg white
spaghetti, cheese, milk

-Chem-plate

-starch indicator (iodine)

-sugar (glucose) test strips

-protein indicator (biurets solution)

Step 1. Reflection

In your journals, attempt to answer the following questions:

1). What nutrients are found in foods like gelatin, bread, milk, and
mountain dew (pop)? Write about each fOOd.

2). Describe how could you find out which nutrients are found in
these foods?

78

3). Why is it important to know what kind of “stuff” is found in
foods?

4). Is it possible for a particular food to have more than one
nutrient? Explain.

5). If you could test a fOOd, what would it be?

Step 2. Action

Place a few drops of the food item to be tested into each well Of
the chemplate.

. Use the indicator solution and place four-five drops of it into the
well with the liquid you are testing.

0 Observe any color changes in the indicator solution.

0 Fill in the data chart below to record your results.

. Does any food item contain more than one type of nutrient?

o How could you design this experiment to test for this? DO it.
What happens?

79

Step 3. Results

Your group’s assigned indicator:

 

Note: YOU will be completing the ENTIRE chart during the class
discussion!

Forms Of Carbohydrate

 

 

 

 

 

 

Substance to Starch Sugar Protein indicator
be Tested indicator: indicator: '
color color
color change change no change no
nO change change chagge

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Step 4. Direct Teaching
Take notes in your journals on your teacher’s explanations Of what

you have just seen. Be prepared to discuss your own ideas with the
class as well.

80

Step 5. Journal Writing — Think and write about the following:

1.

Which nutrients did your food items contain? Explain how you
know.

. How was an indicator helpful in this experiment?

. Based on your Observations, which nutrient does your mystery

food solution contain? Why do you think so?

If a food item did not respond to the indicator, does this mean
that it contains no nutrients? Explain.

. Wait to answer this question until after the class discussion.

Which foods contained more than one component?

Why is it important to know which nutrients are found within
foods?

81

2. Vitamin C - DO You See It?
Purpose:

During this laboratory investigation you will be able tO test for the
presence Of vitamin C using an indicator. YOU will find out if the
way that a juice is prepared affects the amount Of vitamin C in it.

New concepts:

Many foods contain molecules called vitamins. Ascorbic acid, or
vitamin C, is found in a wide variety of foods including citrus fruits
and some vegetables.

The chemical properties Of vitamin C allow it to be detected in given
foods. We will be using an indicator called indophenol. lndophenol
is normally blue when dissolved in water. In this experiment the
chemical indophenol will be used to test for the presence of vitamin
C. When vitamin C is present, indophenol becomes colorless.

Materials:
lndophenol Solution (indicator for Vit. C)

100 ml beaker (one per group)
distilled water
pipettes
50ml beakers which hold sample juices
variety of juices and drinks:
fresh orange juice
bottled orange juice
boiled orange juice
light exposed orange juice
fresh pepper juice
Gatorade/sports drink
10ml test tubes (18 per group)

82

Step One: Reflection
In your journals, attempt to answer the following questions:

1). Rate the following juices for vitamin C content:
(Low High None)

fresh orange juice Sunny Delight
bottled orange juice fresh pepper juice
orange juice exposed to light Powerade

orange juice that has been heated Mountain Dew

2). Considering the above list, predict which drink has the highest
amount of vitamin C. Explain. Which has the lowest? Explain

3). DO you think that the way a food is prepared will change the
amount Of vitamin C found in it? Design a way to figure this out.

4). What do you think vitamin C does for the body? Is it a vital
nutrient? Explain.

Step Two: Action

Measuring the amount Of vitamin C in various samples:

0 Set up your lab area by getting a large beaker with the 18 test
tubes filled with the indicator solution. You will be testing each
sample three times.

0 Choose six sample juices to test. YOU must pick at least three Of
the orange juice samples.

0 Use a different pipette for each different sample liquid being
tested. Place one drop at a time into a test tube containing the
blue indophenol solution. Swirl/invert test tube after each drop.

. Carefully count the number Of drops it takes until the indophenol
solution becomes colorless. Be sure to swirl after each drop.
Record the number of drops and any Observations onto the chart
provided.

0 If your group has added a lot of drops (>20) then keep going until

you note that the color changes from the dark blue to a lighter
color and record this number in the results table.

83

0 Repeat the above steps for each sample being tested. Test each
juice three times and Obtain the average number of drops needed
to change the indicator.

Predict which juice will have the highest amount Of vitamin C:

 

Step Three: Results

 

Type Of Juice Number Of Drops Needed to Change the Indicator

Trial 1 Trial 2 Trial 3 Average Color Solution
turned:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Step Four: Direct Teaching

Take notes in your journals on your teacher’s explanations Of what
you have just seen. Be prepared to discuss your own ideas with the
class as well.

Step Five: Journal Writing — Think and write about the following

1. Which juice/sample had the most vitamin C ? How do you know?
Did this result surprise you? Why or why not.

2. Which juice/sample had the least vitamin C? Does this result
match up with what the liquid is? Explain.

34

. Does the vitamin C amount change depending on the type of
juice? (fresh or bottled) Why or why not?

. What indicator was used? Why do we need to use an indicator to
complete this lab?

. Can the number of drops be determined after one trial? Explain.

. What type of processing may affect the amount of vitamin C
found in a particular food product? Explain.

. If 60mg Of vitamin C is the recommended daily allowance, what

could you dO to ensure that you would consume this daily?

. What is the hardest part about this lab?

85

Teacher Notes: Vitamin C - DO YOU See It?

Introduction:

Many foods contain organic molecules called vitamins. Ascorbic
acid, or vitamin C, is found in a wide variety of foods including citrus
fruits and some vegetables. During this laboratory investigation the
student will be able to test for the presence of vitamin C and be able
to quantify the amount Of vitamin C found within a given sample.

lndophenol will be used to test for the presence Of vitamin C. The
chemical properties Of vitamin C allow it to be detected in given
foods. Hydrogen atoms from a molecule of vitamin C readily react
with chlorine, bromine, or iodine atoms to form other molecules.
lndophenol contains chlorine atoms and it is normally blue when
dissolved in water. When vitamin C. is present, indophenol loses its
chlorine atoms and becomes colorless.

A standard solution Of vitamin C is prepared using vitamin C pills.
This allows the student tO determine the amount Of vitamin C
present in any given food.

Method/Materials:

2,6-dichloroindophenol, sodium salt blender

filter paper distilled water

Pipettes 250 mg Vitamin C pills
baking soda (sodium bicarbonate) test tubes

50 ml beakers electronic balance
variety of juices and drinks spoon

weigh paper test tube rack

Funnel 50 ml Erlenmeyer flasks

Step 1: Create the Vitamin C Standard Solution

Remove a vitamin C pill and crush it between a folded piece Of
weighing paper using a spoon. Use the balance to mass out 0.1
grams Of the vitamin C. Since the vitamin C does not easily
dissolve in water, prepare a 0.1M solution Of sodium bicarbonate by
taking 0.04 grams and mixing it with 10 ml of distilled water in a test
tube.

86

Add the 0.1 grams Of vitamin C to the sodium bicarbonate solution
and mix within the test tube. Once the vitamin C appears dissolved
(there will be some particles at the bottom Of the test tube as these
are the packing materials for the pills themselves), add the mixture
to 90 ml Of distilled water.

Since the concentration Of the vitamin C standard is 1mglml, there
are 0.05mg of ascorbic acid per drop.

Step 2: Prepare the lndophenol Working Solution

Dissolve 100 mg Of the 2,6-dichloroindophenol, sodium salt in 100

ml Of distilled water. Prepare a working solution Of indophenol by

diluting the stock solution by a 1:10 ratio with distilled water. The

indophenol working solution will have a navy blue appearance, and
when exposed to vitamin C, it will become clear.

Step 3: Determine the Amount of Vitamin C Necessary to Turn
the lndophenol Working Solution “Clear”.

. Place 3 ml of the indophenol working solution into a small
test tube. Using a pipette filled with vitamin C standard
solution, carefully count the number Of drops needed tO turn
the indophenol solution clear.

0 Since it takes 20 drops to equal 1 ml, each drop is 0.05 ml.

0 (It should take 11 drops of vitamin C standard or 0.55 mg Of
vitamin C to react with the indophenol.)

0 Record this number for student use.

Step 4: Calculate the Amount Of Vitamin C in the Sample Liquid.

Part I.
(1 mglml) (.55ml) = (y)(average # of drops x .05 ml)
Vitamin C standard Unknown Concentration

Of Vitamin C

87

“y” is then a fractional amount Of the standard . The next step is to
determine how much vitamin C is in the sample being tested.

Part II.
Once “y” is determined, multiply this value times .55mglml. The

resulting value will be equal to the amount of vitamin C in the
sample being tested.

88

3. Lactaid“II to the Rescue!
Purpose:
During this laboratory exercise, you will examine how Lactaid works

on foods that contain the milk sugar, lactose. You will also discover
how Lactaid can be stopped from working.

New Concepts and Vocabulary:

Lactose Enzyme
Digestion Lactase
Lactose intolerant Lactaid
Materials:

Fresh milk or powdered milk
Lactaid or Dairy Ease
glucose test strips
Testtubes

Chem-plates

Glass stirring rod

Hot plate

Step 1. Reflection

In your journals, attempt to answer the following questions:

1). What does it mean if somebody is “lactose intolerant”? How
would a person know if they had this problem?

2). What kind Of sugar is found in milk?

3). What do you think something like Lactaid does to the milk to
allow someone who is lactose intolerant tO drink it?

4). What is an enzyme and what do they do for us?

89

Step Two: Action

0 Every group should have a chem-plate and the wells should be

filled as follows:

A O ‘ 7 .8
U 6] jo II I2-

0 Use the glucose test strips and test for the presence Of glucose

in each Of the wells. Read the strips after 3 minutes and record
the results on the table below.

 

 

 

 

 

 

 

Well Color strip Amount Of Did the
number turned after 3 Glucose in Lactaid
minutes sample work?

 

 

 

 

 

 

 

 

 

 

90

Step Four: Direct Teaching
Take notes in your journals on your teacher’s explanations of what

you have just seen. Be prepared to discuss you own ideas with the
class as well.

Step Five: Journal Writing - Think and write about the following

1. What is the purpose behind using heated lactase in this experiment?
2. What was the max. amount Of glucose found in the milk?

3. What result found while completing the lab supports the idea that
Lactaid works?

4. Did any process speed up or slow down the enzyme, lactase?
Support your answer with evidence gathered from the lab.

5. How do you think our body temperature and the bad effects Of having
a very high fever impact the many enzymes found in our bodies?

6. What is it called when someone cannot digest foods containing the
sugar lactose? DO you know anyone who has this problem?

7. Why do you think this lab has the title that it does?

91

4. Are Nutrients Found in What You Drink?
Purpose:
During this lab activity you will characterize various liquids using a
hydrometer. You will also use various indicators to Observe which
nutrients are present in the different liquids.
New concepts and vocabulary:
Hydrometer Specific gravity
Graduated cylinder Density

Materials:

Various drinks which can include:

Diet pop chemplates

Pop biurets indicator solution
Juices Clinistix or glucose test strips
Gatorade Iodine solution

Milk eye droppers

Ultra Slim Fast 250 ml grad. cylinder

Water food label for your sample

Mystery Drink

Step One: Reflection
In your journals, attempt to answer the following questions:

1). What do you drink during a typical day? You probably had a
glass Of juice during breakfast, some milk on your cereal, maybe a
drink from the water fountain, and a can Of pop during lunch plus
whatever you’re served during dinner. What nutrients are found in
these drinks?

2). Considering everything that you drink during a day, which drink

do you think is the most nutritious? Why? Which drink is the least
nutritious? Why?

92

3). LOOk at the diagrams showing a couple of graduated cylinders
with a hydrometer in them. What do you think is pushing the
hydrometer up? What is the hydrometer reading for distilled water?

 

i

U LA

 

 

 

 

 

 

U

 

 

 

 

 

--4
'A% —
—l

I. /0

 

 

 

 

 

4).

5).

What do you think a hydrometer measures in a given liquid?

What type Of food, a liquid or a solid, contains more nutrients?
Why?

Step Two: Action

Every lab group will be assigned a different liquid tO test. Please
record your groups’ liquid:

Use the hydrometer to find the density Of your group’s testing
liquid

Obtain a chem-plate. You will be using these wells to test the
nutrient values Of the “Mystery Liquid” and the liquid assigned to
your group.

Using the techniques learned previously, test your drink for the
presence Of a particular nutrient and record. Use an eyedropper
to place your testing liquid into the chemplate well. Carefully
add one drop of the indicator solution (Biuret- protein). Record
the color change. DO NOT MIX UP THE EYE-DROPPERS!

Use an eye-dropper tO obtain a sample Of your test liquid. With
the eye-dropper, place four drops Of the sample onto a square
piece Of brown paper. After the sample dries, hold the paper up
to the light and record your Observation. If the paper is “see

93

through” then fats are present. If the paper remains opaque,
then no fats were present.

Step Three: Results

Your groups assigned liquid:

 

 

Well Biurets Iodine Glucose Fats
# (Protein) (Starch)
Yes No Yes NO Yes NO Yes NO

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Results Of Hydrometer Readings:

Fill in the result that your group determined, then wait until the class
discussion to fill out the rest.

 

Sample liquid Density glml

 

 

 

 

 

 

 

 

 

. Results of the food label . Look at the fOOd label for your
group’s sample liquid and fill in the table below:

 

Sample liquid:

 

Calories:

 

Serving Size:

 

Total Fat:

 

Sodium:

 

Total Carbohydrate:

 

Protein:

 

Vitamin _:

 

Vitamin

 

Mineral

 

 

Mineral

 

 

 

 

 

Step Four: Direct Teaching

Take notes in your journals on your teacher’s explanations of what
you have just seen. Be prepared to discuss your own ideas with the
class as well.

Step Five: Journal Writing - Think and write about the following

1. What information does using a hydrometer tell you about that
sample liquid?

2. After the class discussion on the hydrometer results, which liquid
had the greatest density? What nutrients were found in this
liquid (look at the lab results and the label)? Did this result
surprise you? Explain.

95

. After the class discussion, which sample had the lowest density?
Did this result make sense? Why/why not?

. DO the hydrometer results correspond to the nutrient amounts
found within your samples? Explain.

. It is 11:30 and you are really hungry. For lunch, you reach for a
can Of Mountain Dew pop. Would this be a good choice as a
nutrient source? Why or why not. Would Diet Mountain Dew be
a better choice? Explain.

. What types of nutrients (lab) were found in your liquid sample
(the one assigned to your group)? Did these results match up
with the food label information? Explain.

5. Specific Gravity Activity

1. What does a hydrometer do?

2. Predict which juice (shown in the back Of the room) will have the
highest specific gravity.

3. Find the specific gravity Of each liquid:

 

Name of Liquid Specific
Gravity

 

 

 

 

 

 

 

 

 

 

 

4. Did the results differ from your prediction? How.

5. Is specific gravity related to a food’s nutritional value? Why or
why not. (Be sure tO lOOk at the fOOd label.)

6. How can this activity be applied tO nutrition and liquids?

97

6. Whose Urine Is It?

Read the following scenario and then proceed to the reflection
quesflons:

YOU are working as a medical technician in a hospital laboratory.
Your specialty is urine. Since you know how to complete a
urinalysis with accuracy and precision, you have been asked to sort
out a mix-up with the urine samples. It seems that one Of your
coworkers forgot to label a batch Of urine samples and lost the
analysis.

It is up to you to reanalyze them and to match the results with the
proper patients. The good news is that a complete history record
was reported with each patient, and so you are confident that you
can straighten everything with the proper scientific investigation.

Patient histories:

Patient #1 is a twenty-one year Old female and reports that all is
well except that she feels cold a lot. After reviewing her dietary
report, the doctor left a note that she has been only eating
grapefruit for the past four weeks and is underweight for her height
and frame size. The patient has no family history linked to diabetes
or to high blood pressure.

What health clues could be present in her urine?

 

Patient #2 is a fifty year Old male and claimed that he has been
really thirsty for the past couple Of months. When asked if he
exercised regularly, the patient said no. Also the patient
complained Of having no energy yet he has been eating more than
usual. The dietary report showed years Of eating processed foods
with high sugar content. A family history Of heart disease was
established.

What health clues could be present in his urine?

 

Patient #3 is a sixteen-year-Old male who has had kidney problems
all of his life. His dietary report shows a balance Of the major fOOd
groups with plenty of water. The patient also exercises regularly. A
family history showed high blOOd pressure.

98

What health clues could be present in his urine?

 

Step One: Reflection

1.
2.

What is the purpose Of this laboratory investigation?

Which patient above seems to be an easy target for getting type
II diabetes? What clues in the patient’s history helped you to
make this prediction?

. Explain how urine can be used as an indication of a person’s

state Of health.

Step Two: Action

Urinalysis strip

50 ml beaker with urine sample

Clock with second hand (the one on the wall is fine)
Color strip analyzer

Obtain a urinalysis strip, color strip analyzer, and 50ml beaker
with urine. Recorgthe letter Of L_Irine samgle Obtained

Note the time and dip the urinalysis strip into the urine sample for
1-2 seconds (ignore the pH readings)

After one minute, Observe the color change in the strip. Use the
strip analyzer to record ketone and protein amounts onto the
table below.

After three minutes, Observe the color changed for the glucose
portion Of the test. Use the strip analyzer tO record the glucose
levels onto the table below.

Review the patient reports and predict which patient submitted
the urine sample that you analyzed

99

Record the results into your health journal:

Urine sample letter:

 

Time strip was dipped:

 

Time after one minute:

 

Time after three minutes:

 

 

 

 

 

Substance Color turned: Amount
testing for: present:
Ketones
Proteins
Glucose

 

 

 

 

 

Step Four: Direct Teaching
Take notes in your health journals on your teacher’s explanations Of

what you have just seen. Be prepared to discuss your ideas with
the class as well.

100

Step Five: Journal Writing

Think and write about the following questions in your health journal.
Remember to write in complete sentences.

1.
2.

Which patient’s urine did you test? Explain how you know.

Explain how urine can supply clues to show the health of
someone?

Using what you have learned by doing this lab, explain how
nutrition can affect the body. Provide an example for each
situation.

a) Balanced nutrition:

b) Unbalanced nutrition:

. Is it possible for a urine sample to indicate more than one

particular problem? How can/can’t you tell?

. If you could run another test to help you decide which urine

sample you had, what would it be and why?

Write a conclusion statement. Include the following: A) What is
the answer to the original question B) Give your best and most
truthful reason why you think so C) Write about any questions
that you still have even after completing the investigation

101

Fake Urine Recipe

For a class Of thirty students working in pairs, 1 liter Of fake urine is
required. This 2 liter recipe allows for the manipulation of the stock
urine to display various abnormalities which can be measured using
urine test strips purchased through Carolina Biological Supply
Catalog.

Normal Human Urine - 2 Liters

Albumin powder (egg or bovine)
Creatinine

Distilled water

Potassium chloride

Sodium chloride

Sodium phosphate (monobasic)
Urea

0 To 1.5 liters Of distilled water add 36.4 g Of urea and mix until all
the crystals are dissolved.

0 Next, add 15.0 9 Of sodium chloride, 9.09 Of potassium chloride
and 9.6 9 Of sodium phosphate; mix until the solution is clear.

0 Check the pH to make sure that it is between 5 and 7 for normal
urine. If necessary, the pH may be lowered with 1N hydrochloric
acid or raised with 1N sodium hydroxide.

. Use a hydrometer to check the specific gravity Of the urine. The
specific gravity should be within a range Of 1.015 to 1.025. If
necessary, dilute with water until the desired specific gravity is
reached. I used a simple aquarium saltwater hydrometer for this
measurement.

This is the storage stock solution Of “normal urine solution” and may
be kept refrigerated for several weeks or frozen in plastic containers

for months. Before use, the stock solution should be warmed to a
room temperature. Once ready for use, do the following:

0 Add 4.09 Of creatinine and100 mg Of albumin into the 2 liters of
fake urine.

Or

0 TO have the true “smell and color” affect, add 4.09 Of creatinine,
0.4 9 of dried yeast extract broth, and a couple Of drops Of yellow

102

fOOd coloring. Let this mixture age at room temperature for a
couple Of hours to get the desired smell.

Abnormal Human Urine:

Glycosuria — caused by high levels Of glucose due tO diabetes
mellitus, pregnancy, excessive stress, renal tubular damage and
brain damage.

. Add .75 g Of glucose to 1 liter Of stock urine solution

Proteinuria - caused by high levels Of protein the urine and is an
indicator of glomerular damage. In the absence of glomerular
damage, elevated urine protein may result form excessive exercise,
cold exposure and acute abdominal diseases.

0 Add 0.3 g Of albumin per liter or for severe damage add 1.0 g
albumin/liter

Ketonuria — Ketones Of various types, which are normal liver
metabolites, should not be found in detectable amounts in the urine.
Elevated ketone levels are indicative of cold exposure, diabetes
mellitus, dietary imbalances and genetically or chemically acquired
metabolic abnormalities.

. Add 0.1 9 Of acetoacetic acid or 1.0 ml undiluted acetone tO 1.0

liter Of stock solution. I added 4.0 ml Of unscented fingernail
polish remover to get the desired affect.

103

7. Which Drink is the Most Nutritious?

Read and analyze the following labels from various drinks.

Compare the following items in each drink:

Total Fat
Sodium

Sugar

Protein

Vitamins
Calories/serving

Calculate how many teaspoons Of sugar you are consuming with one
serving (Remember that every 11g. sugar = 3 teaspoons sugar).

DRINK A

NUTRITION FACTS
Serving Size 1 cup
Servings Per Container 8

 

Amount per serving

 

 

Calories 120
Total Fat 09
Sodium 0mg
Potassium 420mg
Total Carbohydrate 299
Sugars 28g
Protein 19
Vitamin C 100%
Thiamin 10%
Calcium 2%
Foliate 10%

Phosphorus 2%
Magnesium 6%

 

DRINK C

NUTRITION FACTS
Serving Size 8fl oz
Servings Per Container 4

DRINK B

NUTRITION FACTS
Serving Size 1 cup
Servings Per Container 32

 

Amount per serving

 

Calories 80
Total Fat 09
Cholesterol < 5mg
Sodium 125mg
Total Carbohydrate 129
Sugars 29
Protein 89

 

Vitamin C 2%

Vitamin A 10%
Calcium 30%
Vitamin D 25%

 

 

Amount per serving

 

Calories 70
Total Fat 09
Sodium 55mg
Potassium 30mg

Total Carbohydrate 199
Sugars 169
Protein 09

Not a significant source of Vitamin A, C,

Calcium, or Iron

104

LABEL ANALYSIS:

 

Nutrient

Drink A

Drink B

Drink C

 

Total Fat
L(grams)

 

Sodium
(milligrams)

 

Sugar (grams)

 

Teaspoons
sugar

 

Protein (grams)

 

Minerals
(milligrams)

 

 

Vitamins (m9)
(list them for
each)

 

 

 

 

 

Using the space below, explain which drink above is the most
nutritious. You must have at least four different reasons. Write
your answer in complete sentences.

105

 

8. Calorimetry Demonstration
Step One: Journal Reflection Questions
1.)What is the purpose Of this activity?
2.)What is a calorie?
3.)Which types of foods provide more energy than other foods?
Explain why you think this. (DO they contain different types Of

nutrients?)

4.)Why does the term “empty calories” mean? What type Of food
qualifies as one with this type Of calories?

Step Two: Action

Listen carefully and follow the demonstration. Record the chart and
calculations into your health journals as we go through it step by
step TOGETHER.

Data Table Food item being tested:

 

 

Trial number:

 

Initial mass Of
food and
holder

 

Final mass Of
fOOd and
holder

 

Mass of food
burned

 

Mass Of can
and water

 

Mass Of
empty can

 

Mass Of
heated water

 

Final temp. of
water

 

 

 

 

 

 

 

 

 

106

 

Initial temp.
Of water

 

Temp.
Change

 

Calories in
food burned

 

Calories in 1
gram Of food
burned

 

kilocalories 1
gram Of food
burned

 

 

 

 

 

 

 

 

Calculations:

 

Step 1:

Of

food burned.

 

Example: 48.49 x 4.0 C for .29rams Of food

Or 193.6 calories in .29rams Of food

calories = Mass of water used x Temp. difference for a given amount

 

$0....

How much water did we use?
What was the temp. change in the water?

Now multiply the two numbers together

Of fOOd.

Trial 1 results:

 

 

Trial 2 results:

for grams

Trial 3 results:

 

 

TO get kcal or Calories per gram:

 

Step 2:

Take the answer above and DIVIDE it by the number Of grams
burned.

Example: 907.2calories
.79rams burned

1296 calories/gram

Take this answer and divide by 1000 to convert this value tO
Calories or kcal.
(MOVE THE DECIMAL THREE PLACES TO THE LEFT.)

 

 

 

Step Two Calculations:

Trial 1 Trial 2: Trial 3:

108

Step Four: Direct Teaching.

Take any notes given at this time. Record them into your health
journals. Wait until after the class discussion to complete the
journal response questions.

Step Five: Journal Response Questions

Read each question carefully and then respond in your journal with
COMPLETE SENTENCES.

1. Explain how this activity helped you to find out how much
energy is found within a given food sample.

2. Think about how the food sample burned. Did it burn fast
or slow? Which nutrient do you think is in greatest abundance?
(Hint: How did the way it burned indicate the presence Of this
nutrient?)

3. Why are so many people concerned with how many Calories a
given type of food contains? DO the terms, “calories” and
“nutritional value” 90 together? Explain.

4. Explain the difference between a "calorie" and a “Calorie”?

5. Write a conclusion. Include the following A) What is the answer
to the question? B) What is the best, most truthful reason why
you think so? C) What questions do you still have about the lab
demonstration/investigation?

109

9. Better Cheddar® Label Analysis

. Look at the food label and think back tO your notes. Circle which
nutrients are capable Of generating energy within the body:

Fats Sodium Carbohydrates Protein Vitamin A

How many Calories per gram will carbohydrates provide?
How many Calories per gram will fats provide?

How many Calories per gram will proteins provide?

. Look at the food label. If fats provide 9 Calories per gram,

calculate how many calories are fat calories after eating one
serving?

. How many calories are in one serving Of Better Cheddars?

. What percent Of this food is fat? (show your work....it will be a
division problem)

. What device can be used to determine the amount Of energy
found in a food sample? Explain how it works and include a
picture.

. Which type of flour does this cracker contain? How do you
know?

110

. Which nutrient is in greatest amount when someone consumes or
eats this cracker?

. In your opinion, explain why you think this cracker is or is not a
nutritious snack.

111

APPENDIX D

Student Survey

112

Nutrition Survey

1. How do you define the word “nutrition”?

2. What makes one food more nutritious than another?

3. Which lab activity sticks out in your mind the most?

4. Does knowledge about nutrition influence the food choices that
you make? Explain.

5. DO you think knowledge about nutrition is necessary? Explain.

6. Explain how nutrition can affect your health.

7. What kinds Of activities (in school) help you learn the most?
Numbering from 1 to 6, rank them 1 being the highest and 6
being the lowest.

Taking notes _ Writing in a journal
_ _ Completing a lab _____ Listening in class
Discussion with classmates Watching a

demonstration

8. Which Of the previous activities do you find the most fun to do
while in class?

113

9. What do you think about the nutrition unit that we have
experienced these past five weeks? Check all that apply.

______ boring ______ needs more labs
interesting and fun needs less notes
needs more notes needs less labs

10. Which lab activity did you like the most? Why?

Which lab activity did you like the least? Why?

11. After completing this unit do you find the topic Of nutrition more
interesting or less interesting?

114

APPENDIX E

UCRHIS Approval

115

 

OFFICE OF
RESEARCH
AND
GRADUATE
STUDIES

lniversity Committee on
Research Involving
Human Subjects
(UCRIHS)

Michigan State University
?46 Administration Building
Easl Lansing, Michigan
48824-1046

517/355-2180
FAX. 517/353-2976

The [tire/Jinan State University
IDEA rs institutional Diversity.
Excellence in Action

MSU is an allirnzalive-action,
equal opportunity institution

$1498.93

MICHIGAN STATE

UNIVERSITY

 

October 12, 1999

TO: Merle HEIDEMANN
118 North Kedzie Hall

RE: IRB#99-615 CATEGORY21-A
APPROVAL DATEIOctober 12, 1999

TITLE2USING LABORATORY EXPERIENCES TO TEACH A NUTRITION UNIT TO
7TH GRADE STUDENTS

The University Committee on Research Involving Human Subjects' (UCRIHS) review of this
project is complete and I am pleased to advise that the rights and welfare of the human
subjects appear to be adequately protected and methods to obtain informed consent are
appropriate. Therefore, the UCRIHS approved this project.

RENEWALS: UCRIHS approval is valid for one calendar year, beginning with the approval
date shown above. Projects continuing beyond one year must be renewed with the green
renewal form. A maximum of four such expedited renewals possible. Investigators wishing to
continue a project beyond that time need to submit it again for a complete review.

REVISIONS: UCRIHS must review any changes in procedures involving human subjects, prior
to initiation Of the change. If this is done at the time of renewal, please use the green renewal
form. To revise an approved protocol at any other time during the year, send your written
request to the UCRIHS Chair, requesting revised approval and referencing the project’s IRB#
and title. Include in your request a description of the change and any revised instruments,
consent forms or advertisements that are applicable.

PROBLEMS/CHANGES: Should either of the following arise during the course of the work,
notify UCRIHS promptly: 1) problems (unexpected side effects, complaints, etc.) involving
human subjects or 2) changes in the research environment or new information indicating
greater risk to the human subjects than existed when the protocol was previously reviewed and
approved.

If we can be of further assistance, please contact us at 517 355-2180 or via email:
UCRIHS@pilot.msu.edu. Please note that all UCRIHS forms are located on the web:
http://wwwmsu.edU/unit/vprgs/UCRIHS/

  

David E. Wright, PhD.
DEW: bd

cc: Heather Bradway

116

Parental/Student Consent Form

TO: The parents/guardians of seventh grade students
FROM: Mrs. Bradway (Health teacher)
RE: Requesting permission to use student’s work in a Master’s thesis paper

For the past three years I have been fortunate enough to be spending the summers working on a Master’s of
Science degree which focuses on current biological laboratory techniques in both molecular biology and in
ecology. This learning experience has helped me create a health unit on nutrition, which I hope, can
empower students to make good choices about food

To have a sound thesis I nwd to collect data on the amount of knowledge gained by each student during the
nutrition unit. This 1mit will last approximately four weeks. The data needs to come from the student’s
who will be participating in the Health block class this year. The purpose of this letter is to seek your
permission to use your son or daughter’s confidential scores and responses in my study. Your child’s
pretest and posttest scores will be statistically analyzed to indicate whether or not the unit was effective.
Also, some homework responses may be quoted I want to personally assure you that in the thesis, your
child’s name will in no way be associated with any of her/his scores or written responses. The data
collection process will be virtually unnoticeable and will not effect the students in any way. Your privacy
will be protected to the maximum extent allowable by law.

Mr. Stimac, the 7'h grade Life Science teacher, will distribute and collect this form from your son or
daughter. This is to ensure anonymity about your child’s participation or withdrawal until afier the grades
for the Heath block courses have been determined. If you or your child has any questions about this study,
call me at the middle school at 487-5923. I want to indicate that a withdrawal in no way exempts the
student from doing the same work as everyone else, it just means that I will be Imable to use his/her data in
my thesis.

Thank you for your time and I hope to see you at parent-teacher conferences in November.

Sincerely.

Mrs. Heather Bradway
Hancock Middle School
7‘h Grade Health teacher

 

I give Mrs. Bradway my permission to use my data collected from the nutrition
unit. I understand that Mrs. Bradway will not use my name and that all my student data
will remain confidential.

I do not wish for Mrs. Bradway to use my data in her thesis. I understand I will
not be penalized for choosing to withhold my results.

 

 

Student Signature Date

 

 

Parent or Guardian Signature Date
1 17

HICHIGRN STATE UNIV. LIBRR'
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