THESIS

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thesis entitled

The Use of a Multidisciplinary Project to
Motivate Students in an
Environmental Science Unit

presented by
William J. Hodges

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The Use of a Multidisciplinary Project to Motivate
Students in an Environmental Science Unit

By

William J. Hodges

A THESIS
Submitted to
Michigan State University
in partial fiilfillment of the requirements
for the degree of
MASTER OF SCIENCE

Department of Science and Mathematics Education
College of Natural Science

1997

ABSTRACT
The Use of a Multidisciplinary Project to Motivate
Students in an Environmental Science Unit
By

William J. Hodges

Many studies on multidisciplinary teaching have claimed that there are benefits for
learners. However, quantitative documentation of such claim is difficult to find. This
work will examine and analyze how the inclusion of a multidisciplinary project to end an
unit affected the learning of eighth grade students.

The environmental unit, entitled “A Household’s Efl‘ect on the Environment”
focused on the issues of acid rain, lawn chemical use, and waste disposal. Many
demonstrations and laboratory exercises were used to illustrate how a child’s home may
contribute to local pollution. At the end of the unit, the students used their knowledge
and data in a mock trial within a social science class. Examination of the data shows that
the students learned the material as well as other units on their immediate formal
assessment, but retained the information better than similar units. The presence of the trial

also encouraged students to explore resources beyond the classroom.

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all"

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ACKNOWLEDGEMENTS

I would like to thank the following people:

My wife, Kelly, for her support and statistical expertise in the completion of this
four-year process.

My parents, for their unconditional love and undying support in all that I endeavor
to do.

Beth Grzelak for providing the impetus for this undertaking and providing me with
the resources needed to take scientific experimentation into a social science setting.

All of the professors who shared their knowledge with me so that I may share it
with my students. These people include Merle Heidemann, Ken Nadler, Marty
Hetherington, Howard Hagerman, Sheldon Knoepsel, Paul Hunter, and all of the experts
who presented at the Frontiers sessions and provided invaluable information and ideas.

Steve Yzerman for showing that perseverance and hard work can attain any goal,
no matter how difficult the route.

To students past, current, and fixture: may I enrich your life as much as you enrich

mine.

iii

TABLE OF CONTENTS

LIST OF TABLES .......................................................... vi
LIST OF FIGURES ......................................................... vii
INTRODUCTION .......................................................... 1
Instructional Philosophy ........................................... 1
Reason for this Study .............................................. 2
Demographics ...................................................... 7
IMPLEMENTATION OF UNIT ....................................... 8
Objectives of Unit .................................................. 8
Weekly Outline of Unit ............................................ 8
New Techniques ................................................... 11
Analysis of Activities ............................................... 12
EVALUATION ............................................................ 23
Pretest ............................................................... 23
Posttest Essay ...................................................... 24
Short Answer Posttest ............................................. 26
Comparison with Different Assessment ......................... 27
Final Exam .......................................................... 28
Special Education Students Performance ....................... 29
Informal Interviews ................................................ 3O
Informal Assessment of Trial ..................................... 32
CONCLUSIONS ............................................................ 33
BIBLIOGRAPHY ........................................................... 36
APPENDICES
Appendix A Student Activities
Al Making a Subdivision ............................ 39
A2 What Happens in a Landfill ..................... 40
A3 The pH of Common Substances ................ 41
A4 Production of Acid Rain (LAB DEMO) ...... 42

A5

A6
A7

A8

A10
All

Appendix B
Appendix C

C1
C2

The Effect of Acid Rain (Sulfur Dioxide)

on Plant Life Teacher Demo .................... 43
Effect of Acid Rain on Brine Shrimp .......... 44
Yom' Household’s Sulfur Dioxide

Production ........................................ 45
Large Scale Pond Eutrophication Demo ...... 47
The Effect of Fertilizer on Grass Crops ....... 48
Efi‘ect of Lawn Runofl‘ on Brine Shrimp ...... 49
Making Paper ..................................... 51
Daily Outline of Unit ............................ 52
Assessment Samples

Short Answer Test Questions .................. 55

Student Sample of Essay Posttest Answer. . . 56

LIST OF TABLES

Table 1. Statistical Analysis of Environmental Assessment and Electricity Test 27

Table 2. Comparison of Regular Education and Special Education Scores 30

LIST OF FIGURES

Figure 1. Student Scores on Essay Pretest and Posttest 25

Figure 2. Student Success on Final Exam 29

vii

INTRODUCTION
Instructional Philosophy

Science is the pursuit of explanations and patterns based on careful observation.
Scientists devote their time and energy into studying the myriad of phenomena that the
universe has to ofl‘er. In order to produce precise and accurate results during their studies,
they must carefully observe. This observation depends on controlled experiments, precise
treasm'ing devices, and patience. Ultimately, these observations lead to explamtions of
the natural world. Any science class should mimic the work of practicing scientists and
revolve around the practice of discovery, observation, and explanation.

There are many techniques and philosophies in educational literature which claim
to transform students into scientists. Depending on the teacher’s skills and the audience’s
abilities, all of these approaches can work when the right combination is present. Teacher
Keith Caldwell professes this best with his quote on the individuality of each classroom
environment. He states, “The bottom line in teaching is, and will always remain, the art
and the genius of that particular teacher, in that particular classroom, with that particular
group of kids, on that particuhr day.” (Caldwell, 1996)

In my classroom, I have embraced the conceptual change model of instruction.
The conceptual change model is very similar to constructivism. In constructivism, the
instructor must realize that learners bring their own experiences into the classroom. This
prior knowledge is present and will afi‘ect all other information presented to them. The
students will attempt to use their prior knowledge in order to make sense of experiments,

lecture material, and all other forms of instruction. This prior knowledge needs to be

accounted for, and students must be shown evidence that their origiml false explanations
do not work (Schulte, 1996). Conceptual change works by forcing students to become
uncomfortable with their own misconceptions, forcing them to gain some understanding of
the problem to view a scientific concept as possible, and then apply this concept to other
situations (Muth and Alverman, 1992).

To help them, I provide discrepant events, series of questions which aid students in
connecting concepts (scafl‘olded questions), and a safe environment where they feel free to
guessandmake mistakeswhiletryingto explainwhyandhowthingswork. lama
facilitator to their learning, not the center of it. Students work in c00perative groups in
order to explain how and why things happen. We do not use textbooks, for the textbooks
on the market are collections of facts. I want my students to conduct investigations using
the physical world as their laboratory and actually discover the answers for themselves.
Instead of relying on a textbook, the students create their own in their lab notebook. All
of their notes, laboratory experiments, classwork, and review go into their notebook.
Every two to three weeks the notebook is collected and assessed for completeness and
quality. This is the instructional approach which I am comfortable with for my audience
and for my style. However, I am intrigued by additional methods of instructing students.
Reason for this Study

In 1993, my school decided to try interdisciplinary teaming at the eighth grade
level. Each team would consist of a mathematics, English, soc'ml science, and science
instructor. This decision was based on two factors: 1) interdisciplinary teaming had

received a great deal of press as being a positive classroom experience for middle grade

level students and 2) we had time and resources allotted to us fi-om Michigan State
because we were a professional development school. Allowing our students to be a part
of a smaller group (122 students) within a large building (832 students) made sense for
many reasons.

Our first year in teaming was focused on learning one another’s curriculum as well
as attempting to take advantage of the non-curricular aspects of teaming. As the literature
suggested, we learned that team teaching did lower student alienation in the school
(Arhar, 1992) and were able to provide consistent goals, outcomes, and procedures
(Stevenson, 1992). We also saw other benefits of teaming which were predicted by the
research. The teaching staff in the eighth grade cooperated better (Green, 1989),
discipline problems were fewer and easier to handle (Stevenson, 1992), and because of the
availability of other teachers within the team, we were able to identify individual student
problems and deal with them quickly.

The more learner inforrmtionthat canbe shared, themore likelythe learning

problems can be anticipated and reduced. The more individual student information

that a teacher possesses, the more likely an effective classroom enviromnent can be
established for meeting the unique needs of each middle level learner (Allen, etal.,

1993).

During that first year, we were able to “create small connnunities for learners” where the
students felt like a valued member of a group (Carnegie Council, 1989). We provided a
safe, responsive community for our children. However, we still did not make the
connection between curricula

The goal for the following year was to find connections between the four core

curricula and create interdisciplinary units. “Teaming in a school, however, is affected by

a great many variables over which the team has no control.” (Stevenson, 1992) Michigan
State was forced to drop our school as a professional development school, and we lost the
time and resources needed to implement true curricular teaming. This was upsetting,
because I wanted to see if interdisciplinary teaming did indeed afl‘ect student achievement.
Because ofthemanyvariables inherent to teaching andalack ofastandardized
measurement tool to evaluate students’ abilities to make connections, the literature does
not provide a satisfactory answer. “Does teaming make a difference in students
outcomes? The answer is that it probably does, but not in direct discerm'ble ways.”
(Arhar, 1989) The American Association for the Advancement of Science (1989)
encourages teachers to use interdisciplinary approaches, but does not detail the benefits.
As a researcher, I wanted to explore how incorporating an interdisciplinary aspect into a
unit would affect my students’ learning. The literature abounds with articles and stories
documenting how important interdisciplinary teaching is for students, yet does not provide
me with clear evidence of what my students will receive fiom this form of instruction.
Onlybyactuallyhaving my studentspresent informationinadifi‘erentclassroomwith
different expectations and goals, will I be able to assess the bridging of curriculum.

The social science teacher in my team had a very similar educational background
as myself and was also curious about the benefits of interdisciplinary teaming. Her class,
entitled Rights and Responsibility, was a social science class concerned with government,
law, and economic issues. She expressed an interest in discussing some environmental
issues. Being a physical science teacher, I was hesitant to accept the idea at first. My

curriculum is comprised of the Physical Science Objectives for High School in the

Michigan Essential Goals and Objectives for Science Education (K-12) (Michigan State
Board of Education, 1991). I could not compromise my objectives for the sake of an
interdisciplinary unit. However, closer examination of the objectives provided a
revelation.

Therewere fourobjectives inthe state science curriculumwhichwasnot being

adequately covered in my classroom.

0 Trace,toanoriginalsource,theenergybeingusedbylivingthingsand

machines.

0 Describe how common materials are made and disposed of or recycled.

0 Evaluate alternative long range plans for resource use and byproduct disposal

in terms of environmental and economic impact.

0 Analyze properties of common household and agricultural materials in terms

of risk/benefit balance. (Michigan State Board of Education, 1991).

These four objectives were not being covered in my classroom, and each one of them
concerned environmental issues. However, the four objectives were also very broad. I
could spend an entire year covering the details of recycling, resom'ce use and disposal, and
analysis of materials used around the house. I needed to cover the objectives with specific
examples that would allow students to learn the objective and apply that objective to novel
situations they may encounter later.

Since I had a wide range ofexamples which I could bring into the class, I decided
to focus on issues which are related to students and their homes. The use of everyday
problems and materials which they encounter daily would add meaning to the unit. I
decided to focus on three main areas: the creation and results of acid rain, the positive
and negative efi‘ects of fertilizers and pesticides, and the disposal of solid wastes.

Furthermore, I wanted to let the students see both sides of these environmental issues and

realize that there is no right or wrong answer. Too often, students take the opinions of
their instructor and regm‘gitate them on a test. I would try to present both sides
impartially and let the students make their own decisions.

In researching the rmterial I wanted to teach, I discovered that literature abounds
withinformationonacidrain, use andmisuseoffertilizersandpesticides, landfills, and
recycling. Much of the details of this information is above middle school students, but I
was able to sift through this material and find useful ideas from the following resources.
Acid rain inforrmtion was gathered from Hollander and Brown (1992), Harte (1992),
Treshow and Anderson (1989), Winner, Mooney, and Goldstein (1985), Mason (1991),
O’Neill (1985), Johansson, (1992), and fiom the Pace Center (1990). The Lansing Board
of Water of Light was also very generous with information concerning the amount of
sulfur dioxide which they emit from their coal burning plant (Stickler, 1996). Information
about fertilizer use came fi'om Mason (1991), Miller (1991), Abel (1989), Irvine and
Knights (1974), and O’Neill (1985). Pesticide use information came fiom Leng (1985),
and Goolsby and Bataglia (1995). I also found some good recycling information fi'om Kut
and Hare(1981). All of these sources were used to provide hard numbers and details to
the experiments and discussions concerning the experiments.

Once the rmterials were gathered, a connection between the social science class
and the environmental issues had to be formed. True interdisciplinary teaming, where
both teachers can provide instruction concurrently on the same topic, was not a possibility.
We lacked the facilities and flexibility within our building to accomplish such team

teaching. Instead, we opted for what is called multidisciplinary teaming. Both teachers

would approach a theme within their own discipline (Stevenson, 1993). I would help my
students nuster the science concepts and they would prove their mastery in another
classroom. The would present and defend arguments concerning fertilizer and pesticide
use in their social science class. This presentation would be in the form of a mock civil
trial, and the students would need to demonstrate their knowledge in order to influence
their peers. Not only would they need to know the material, but they would need to know
it well enough to teach and convince others of their mastery of that material. In addition
to measuring their proficiency in the subject matter, I wanted them to display their
proficiency in a different setting.
Demographics

'Ihejuniorhighwherethisunitwastaughtisanuniquebuilding. 'lheschoolbody
is entirely eighth (424) and ninth grade (417) students. The commtmity is a suburb of a
large urban city and has undergone considerable growth and change in the past decade.
Seventy-five of the students (11%) received free or reduced-price hmches (our indicator
of financial hardship) in the 1996-97 school year, and we had 105 special education
students (24%). There is a small but growing minority population (7.5%). I taught five
sections of physical science, comprising of 122 students. Fifteen of my students were
special education students (12%), and 10 were minorities (8%). For this unit, three
students did not attend school, and two had just immigrated fiom Russia and did not

speakEnglish. Iwillnotusethose scoresinmyanalysis.

IMPLEMENTATION OF UNIT

The three week unit was presented to the students at the end of January. The
studentshadjust finishedtheirworkonchemistryandhadtakenafinalexamforthefirst
semester. An unit on electricity would follow. Because of this sequencing, ideas from
the chemistry unit such as chemical changes and bonding would be reinforced. Similarly,
all of the work in the environmental unit concerning electricity production was useful in
introducing the electricity unit. At the end of the school year, students answered
questions about the unit on the final exam and six students were inforrmlly interviewed.
Objectives of Unit
1. Students will rmster the following MEGOSE Objectives
0 Describe how common materials are made and disposed of or recycled.
0 Evaluate alternative long range plans for resource use and byproduct disposal

in terms of environmental and economic impact.
0 Trace, to an original source, the energy being used by living things and machines.
0 Analyze properties of common household and agricultural materials in terms

of risk/benefit balance. (Michigan State Board of Education, 1991).
2. Students will be able to demonstrate this information in the form of a written essay as
well as in a mock trial setting.
Weekly Outline of Unit

Special note: All of the activities mentioned throughout this work, with the
exception of “Making Paper”, were created for the unit through research and
development at Michigan State University during the summer of 1996. A detailed list of

each day’s activities can be found in Appendix B.

Week One:

Theunitstartsbyintroducing studentstotheroletheirhouseplaysinthe
environment. This is accomplished through a pretest essay and the worksheet “Making a
Subdivision” (Appendix A1). The students then start a landfill project which will operate
during the entire unit. The week concludes with an introduction to acid-base relationships,
two demonstrations which show students how acid rain is produced and how it affects
plants, and an experiment which demonstrates how acid rain can damage aquatic
invertebrates.

Week Two:

The week begins with an overview of the previous week’s acid rain activities and
presents students with the challenge of calculating how much sulfur dioxide is produced
bytenoftheir appliances. Studentsthenspendtherest ofthe weekperformingand
observing experiments with fertilizers, pesticides, and insecticides.

Week Three:

Students recycle paper and observe the results of the landfill experiment. They
then compare the two different forms of solid waste disposal. After a day of review, the
students then take the short answer posttest (Appendix Cl) and the essay posttest
(Appendix C2).

Week Four:

Whilelwasteachmgtheenvnonmentalunh,mestudentswerekarnmgmedetafls

of the law system in their social science class. The instructor of the class had already

10

informed students about the three branches of government and lmd covered the executive
and legislative branches. Her focus during the three weeks of my environmental unit was
the judicial branch, and she wanted students to appreciate how a trial works. For their
final assessment, students would have to participate in a mock civil trial, Students were
then randomly assigned to the roles of defendant, defense lawyer, defense witness,
plaintiff, prosecutor, prosecution witness, or jury member.

Thetrial wasacasebetweenthefarmersofafictitious islandversusthe
Environmental Protection Agency of the island. The “island” was the homeland of our
team’s students, and the students had already developed a government and constitution for
their island. In this civil case, the farmers were suing the EPA because the EPA banned
the use of fertilizers and pesticides on the island. The purpose of the trial was to provide
students with a novel setting where they could use information that they gathered in
science class. During my assessment of the students, students were preparing their court
cases in their social science class. After the final assessment of the unit in my science
class the students then participated in the mock trial in their social science class.

The trial took two days to complete. Oflicial court protocol was followed, and
students were sworn in, jurors walked in as a group, and all rose when the judge (the
social science teacher) entered the courtroom. On the first day, the students made
opening statements and the prosecution stated their case. On the second day, the defense
was able to state their case, closing statements were issued, and the jury deliberated to
reach a verdict. All ofthe elements ofa real trial were present, including spirited

rebuttals, objections, and cross examinations.

11

New Techniques

The primary new teaching technique tried in presenting this unit is called
‘finultidisciplinary teaming”. (Stevenson, 1993) We did not actually teach with
interdisciplinary nrethods, for this involves teaching both subjects in one classroom.
Instead, we approached a topic through two different classes and reinforced each other’s
work. Due to small classrooms and limited accessibility to students when they are not in
omclassroomsthiswasthebestwecoulddo. Inthesocialscience class,thegoalwasto
givethestudentsanactualargumentwhichhasbeenandwillcontinuetobeasoru'ceof
disagreement in our law system While grading the arguments, the social science teacher
was more concerned with the details of the students’ roles than the use and knowledge of
the experiments. I was interested in assessing how well my students understood the
experimentsandresultsandwhethertheycouldusethoseresultsto defendtheirside. The
trial was not only going to test how well the students understood the material, but also
reveal the benefits and disadvantage of allowing curricula to “flow through walls”. The
students were not formally graded in my class for their role in the trial.

In addition to the multidisciplinary focus, I tried some other different techniques
during the teaching of this unit. One was the inclusion of long-term experiments. Being a
chemistry and physics class, most of our experiments require only one to two days. The
“What Happens in a Landfill” (Appendix A2) experiment, the “Large-scale Pond
Eutrophication Demo” (Appendix A8), and “The Effect of Fertilizer on Crop Grasses”
(Appendix A9) required foresight and time in order to get the desired results. Because of

this time constraint, I started and maintained the second two ofthe activities while

12

students observed and gathered the results. This compromise reflects the tight schedule
under which teachers operate.

The final innovationl attempted was the use ofan essay pretest and posttest. One
of my goals was for students to leave the cormse being able to make logical decisions
about electricaL fertilizer, and pesticide use. Then, they were assessed on their opinion in
an oral format (the trial) and in writing-«the essay. While I was worried about my
students with writing deficiencies, I was gratified to see if they could present an argument
and back it up with evidence gathered from my class. The essay format gives little
structure, which could be either beneficial or disastrous to individual students.

Analysis of Experiments, Demonstrations, and other Hands-on Activities

Making a Subdivision (Appendix A1) The purpose of this activity was to take the
simple process of starting a neighborhood and look how it adversely affects the
environment. This assignment served as a springboard for other environmental issues
which seem simple at first, but involve a series of steps. Since our community is rapidly
growing, the students have observed the creation of many new subdivisions. These
changes bring about severe changes in the local environment, and I wanted the students to
recognize how drastic these changes really are. The students found it quite diflicult to list
the ways in which a subdivision could affect the environment, and focused on the
destruction of wildlife habitat. They were also obsessed with the destruction of trees
leading to a lack of oxygen. This was a good misconception to address, for trees only
produce a small portion of the world’s oxygen supply. After this is addressed, the

students answered a series of scafl‘olded questions which enable them to conclude that the

13

creation of a subdivision leads to increased local temperatures and the decreased
replenishing of aquifers. While the students understood this idea, this portion often got
lostintheassessment essay. Ifeelthiswasbecausewe spent onlyone dayonthe lesson,
it occurred at the beginning ofthe unit, and there wasn’t a quality hands-on activity to go
along with it.

What Happens in a Landfill? (Appendix A2). The purpose of this simple activity
was to show students how a landfill works and use this informration to compare the
advantages of landfills with the advantages of recycling materials. The students were
quite unaware ofthe details which go into the creation ofalandfill, and I was able to tie in
rmny earth science concepts concerning clay and groundwater. Although the students
predicted that the food would decompose quickly while the rest of the garbage would
take longer, they were shocked when the paper did not decompose appreciably. Due to
their cmiosity, we maintained the landfills for the duration of the year and discovered
my wonderful fimgi. The role ofthe fungus as a decomposer was useful in reinforcing
the role of bacteria in decomposing dead plant life in ponds, which leads to eutrophication.
This activity proved useful to many aspects ofscience and was very useful in generating
student interest and questions.

The pH of Common Substances (Appendix A3). The purpose of this large group
activity was to provide meaning to the pH scale. After explaining what it means to be an
acid and a base, we created the 1-14 pH scale. The students thentested different
common household and hboratory chemicals and placed them on the scale for future

reference. ThisacfivitywasusefiflbecauseteflmgstudentsthatlermnjtucelmsapHon

l4

hasno meaning. Telling studentsthatthesulfirric acidusedinclassisonlytentimesmore
acidic tlmn lemon juice does have meaning for them. This laboratory exercise was needed
to provide background for the acid rain experiments and discussion. The

disappointment of this activity was that the students had difficulty with the logarithmic
scale. For example, few could reason that a substance with a pH of 5 was 100 times more
acidic than a substance with a pH of 7. This was their first introduction to logarithmic
scales,andtheywilllearnaboutitinearthscience(Richterscale)nextyearaswellasin
mth classes, so I am not overly concerned. As a result, my students did not get the
related question correct on the short answer test.

On a positive note, though, most of them walked away fi'om this lesson with a firm
understanding that strong bases and acids are both dangerous, and their misconceptions of
all acids being dangerous and all bases being safe were corrected. This demonstration was
also important because it provided the opportunity to explain that normal rain water does
not have a pH of 7. It actually has a pH near 5.6. Therefore, rain water is naturally acidic,
and scientists do not consider precipitation to be acid rain until the pH gets below 5.6
(Harte, 1992). Thisisanirnportant ideawhenstudyingacidrain.

Production of Acid Rain (Appendix A4). This demonstration showed the students
tint the burning of charcoal produces an acidic gas. Many students had identified that
using electricity was damaging to the environment in the pretest, but very few associated
the burning ofcoal as being the culprit. Furthermore, they had no real idea that acid rain
was the chief type of air pollution created by electricity-generating factories. The first few

lab questions led to a discussion of ozone depletion and global warming, but then turned

15

to the acid rain implications. For dramatic flair, I used Bromothymol Blue as the pH
indicator so the students could see the color change produced by the burning of charcoal.
Ialso testedthewaterwitthpaperto firrtherprovethatthepHchanged(two testsare
better tlmn one). When I interviewed my students, many of them listed this demonstration
as their firvorite. They enjoyed the elaborate setup for the experiment and they felt that a
connection between electricity use and acid rain production had been establislwd.

The Effect of Acid Rain on Plant Life (Appendix A5). This demonstration showed
the effect of sulfur dioxide on plant life. Poinsettias were used to provide a very dramatic
indication of the bleaching and dehydration of leaves and flowers when plants are exposed
to sulfitr dioxide. While this demonstration was very dramatic, it did have its drawbacks
scientifically. The students were able to explain reasons why placing a plant in a bag with
sulfin‘ dioxide did not represent how acid rain afl'ects plants in the wild. Too concentrated
ofagas, sulfurdioxide not dissolved inrain, andlack ofnaturalconditionswerethemost
common student concerns with this experiment. I was most impressed by the students’
abilityto reasonwhytheplantwasdamaged. Byexaminingtheleaveatheywere ableto
deduce that it looked like the plant was dehydrated. In fact, sulfirr dioxide damages plant
stomata and hinders a plant’s ability to control water evaporation. (Majemik and
Mansfield, 1970) I was able to use the students’ observation to discuss the damaged
stomnta. This demonstration really hit home when the students learned tlmt the United
States made over 23,699,000 tons of sulfur dioxide in 1990 (Pace Center, 1990).

Eflect of Acid Rain on Brine Shrimp (Appendix A6). The purpose of this

laboratory experiment was to show that acidic aquatic conditions can destroy life. Brine

l6

shrirnpwereusedbecausetheyareeasyandcheapto growandwillshowchanged
behavior when placed in acidic conditions. This experiment was very effective in showing
students the dangers ofacid rain. They immediately saw the reactions ofthe brine shrimp
and wanted to remove them fiom the conditions when they started to show distress. The
most importantpartsofthislabcamethroughinthediscussion. Thediscussionledto why
the death of invertebrates would be bad for a pond or lake. The students were able to
generate the idea that the invertebrates are food for larger invertebrates and vertebrates,
and that the entire pond could die due to the disruption of the food chain. All of the
classes had the prior knowledge of food chains and readily assimilated this information
into their previously formed schemata. When doing this experiment again, I would change
my questioning technique on the experimental questions. Instead of asking “What would
happen to the rest of the animals in the lake?”, I would ask the following two questions:
“What wouldhappento acreaturethat eatsthebrine shrimp?”and “Howcouldthis
eventually effect a large predator?” . Even though we discussed the details of the food
chain, my eighth grade students seldom take notes on discussion and could have used
these ideas in their notes.

The discussion of this activity also presented an opportunity to talk about models.
Brine shrimp are not native to 01m lakes: they are saltwater creatures. They were used
becausetheyare simpleandcheaptoraiseandtheyreactto acidrainmuchlike fi'eshwater
invertebrates. The use of the brine shrimp act as a model for freshwater invertebrates was

testedinthe students’ comtcaseaandtheevidencewasvalidatedbythejurywhenthe

17

lawyers could defend the importance of mrodels. When the lawyers couldn’t defend the
use of models, the experiments were not accepted as valid evidence.

Your Household ’s Sulfur Dioxide Production (Appendix A 7). At this point, the
students have discovered that when coal is burned, sulfur dioxide is produced and
contributes to acid rain. They have observed the effects of acid rain and sulfur dioxide on
plants and animals. This assignment ties their own world into the process, as the students
go home and calculate how much sulfur dioxide is actually produced fi'om ten of their
appliances. The number they calculate is per day, and they then project it for a month and
ayear. The studentswere anamdatthenumbersthey were calculating. Manystudents
calculated values over 25,000 grams/year. This calculation was only for ten appliances,
and for only one household. When students made the connection to the “Effect of Acid
Rain on Plant Life” experiment and the damage that less than a gram of sulfur dioxide had
on the plants, they truly saw a need to stop wasting electricity and look for alternative fuel
sources. At the same time, when asked if we should stop using electricity, the students
emphatically answered no.

This homework assignment proved very diflicult for my students who have
difliculty with math and following directions. Before assigning it, I checked with the math
instructor in my team, and she felt that the directions were clear and that our students
should be able to manage it. However, many students fell short on the assignment. I think
that this was a very good connection between the students’ lives and the material, but I
need to find a way to make the math more accessible for students who struggle with

numbers.

18

Large-scale Pond Eutrophication Demo (Appendix A8). Before the teaching of
this unit, most students did not feel flat fertilizers could cause any damage to the
environment. Thefewstudentswho didthinkthatfertilizerswereharmfirlstatedthatthey
were poisonous to humans or animals. During the trial, some students even used data
concerning “Blue-baby syndrome”, a condition which arises when too much nitrate gets
into the water or food of babies. The truth is, the last case of Blue-baby syndrome
occurred in Britain in 1972, and the last fatal case was in the 1950’s (Emsley, 1994).
Likewise, nitrates have not been found to be carcinogenic. Therefore, my students did not
have any idea that fertilizers were dangerous to the environment, or worse yet, they felt
that the principal danger was fertilizer consumption. This demonstration of a month-long
experiment helpedthemunderstandthetrue dangeroffertilizers.

Two aquaria were filled with pond water and aquatic plants. I placed 200 ml of
Miracle-Gm Q fertilizer into one of the tanks every day for a month. During this time,
curious students observed the changes. When we were ready, the class formally viewed
the results of the experiment and answered questions about their observations. The
plants in the fertilized tank looked very healthy, but there was an abundance ofblue-green
algae onthewallsofthe tank. Thccontroltankheld healthyplantsanddidnot havethe
blue—green algae.

The questions on the experiment focused on two areas: 1. How could fertilizer
fiom yoru' lawn get into a pond or river?, and 2. Why would this be bad for the pond?.
Most students needed scafl‘olded questions to help them make the connection between

fertilizer use and pond eutrophication. First, we had to discuss that storm drains usually

l9

empty into large bodies of water, not into sewage treatment. Students could then
understand how the fertilizer from their house can get to the bodies of water, but they still
needed to understand the process of eutrophication. Blue-green algae is disgusting from a
student’s point of view, but the plants looked good. After discussing the ideas that blue-
greenalgaeisnot eatenbymanycreatures, andtlat whenalloftheplantlifediedithadto
be decomposed by oxygen-using bacteria, students discovered that the growth of too
many plants can eventually lead to a pond losing oxygen due to the decomposition by
bacteria. This was a diflicult idea to comprehend, for most students equated the
production of plants with the production of oxygen. Students eventually did master it,
though, and were able to rationalize the series of steps that lead to the creation of a
eutrophic pond in both the essay and short answer exam. This was probably the hardest
connection for students to make because the aquarium did not actually reach the point of
decay. However, they were able to use their reasoning skills to master the material.

Effect of Fertilizer on Grass Crops (Appendix A9). This experiment was the
result of a month of growing and fertilizing wheat, oats, and barley seeds. The students
observed the results of the crops’ growth and took measurements of individual plants and
observations of the plot as a whole. The purpose was to show that fertilizer does indeed
increase biomass. Results of this experiment were disappointing, for only the barley
survived inthe trays. I feelthat the lack ofsuccess inthe wheat andoatsplotswasdueto
poor drainage: the trays used to grow the seeds did not have drainage holes. The barley
trays were very successful, and students could see a marked difference between the

fertilized and unfertilized plants. This was an excellent experiment to reinforce the ideas

20

of control and experimental groups, experimental design, and address the common
misconception that fertilizer is plant food. The students were easily convinced that
fertilizer causes plants to grow faster, larger, and more bountiful. Therefore, this
experiment simply confirmed previous experiences.

Effect of Lawn Runoflon Brine Shrimp (Appendix A10). The purpose of this
experiment was to show that insecticides kill most invertebrates, including organisms
whichliveinponds. Thefertilizerandherbicidedidnotkillthebrineshrimp,butthe
insecticide did. Students were asked to use their previously gained knowledge to make
connections as to how the pesticides could get into the pond and how the death of
invertebrates could affect the pond. l was very pleased that students were able to take the
previously gained material and apply it to the new situation. The students also read an
article which explained that insecticides were harmful to beneficial insects and suggested
more ecologically fiiendly ways of controlling insect pests. I was very disappointed that I
did not have a good demonstration showing the benefits of pesticides. During the trial and
student interviews, it was revealed that most students were completely against the use of
pesticides. A good control/experimental group experiment might have helped them see
the benefits as well as the disadvantages of the pesticides.

Making Paper Lab (Appendix All). This activity was modified fiom the ideas of
the American Forest Foundation (1993). The purpose of this laboratory experiment was
to show students the steps of recycling waste paper into new paper. The results were
messy and two drains were clogged, but the students enjoyed thenaelves and worked on

perfecting their paper so that they could be in the running for extra-credit points (given to

21

the best paper of each class, voted on by an unbiased panel of teachers). The results were
very positive. Students realized that recycling paper is costly, takes time, and uses
electricity, which causes further pollution. They also were dissatisfied with the color of
the paper. This led to a good discussion on the addition of chemicals and the pollution
that could be caused by this process. Students were able to contrast landfills with
recycling and were able to see the benefits and disadvantages of both.

The trial. While the trial was not wrthm the confines of my classroom, I was able
to observe the process both directly and indirectly. I was unable to attend the first day of
thetwo-daytriaLbut studentsupdatedmethroughouttheday. Iwasableto watchthe
second day of litigation, and I reviewed both days on videotape. Overall, the students did
a very good job presenting results and interpreting data. They were able to question
methods of experimentation (Why were brine shrimp used when there are no brine shrimp
in the ecosystem in question?), use resources outside of the classroom as evidence
(intemet material as well as other texts), and critically examine each other’s presentations.
What was most impressive to me was that the trial generated a great deal ofexcitement
which caused students to explore details beyond the requirements of the class.

Many students spent large amounts of time finding additional resources which
would help them with the trial. My slogan of encouragement throughout the unit was
“Knowledge is Power”, and the more information that you know, the better your
presentation and defense of it will be. Students scoured the lntemet, journeyed to
h’braries, and consulted many primary texts and anecdotal references such as Rachel

Carson’s Silent Smng' . Students returned to my classroom during lunches and before and

22

after school to conduct their own experiments on brine shrimp and plants. Some tried
difi’erentpesticidesto seeiftheyhadthe sameefl‘ectasSevinobrandthatwasusedin
class in our experiments. Many connections were made, and students defending the
farmers’ interests argued that mowing lawns damages the environment, yet there are no
laws outlawing the mowing of lawns. This strategy was successful, because the jury was
placed in the position of making a judgment concerning relative levels of environmental
damage. The students gathered much information and used that information to their
advantage. “Attorneys” who were not prepared had great difliculty refuting their
opponents’ testimony, and students realized that the “Knowledge is power” slogan was
very true. Those who researched and anticipated the other side’s arguments were

successful.

EVALUATION

Studentswere evaluatedinmanydifl‘erent waysduringthisunit. Thepretest for
the students was an open-ended essay on how their house affected the enviromnent, and
halfof their posttest was a similar essay, specifically a letter to a fi'iend explaining how
their fi'iend’s house affected the environment. Students were also given a short answer
posttest, which was more akin to their normal posttest. I also informally assessed the
success of the unit through observations of the trial. These sessions allowed me to really
observe how well my students understood and were able to use the infomration they had
gathered in class. Finally, at the end of the year, I informally interviewed six students and
comparedhowthe studentsperformed onafinalexamwiththeirperformancetotherest
of the second semester.
Pretest.

The pretest demonstrated that students had many misconceptions and showed
that they had not considered the role flrey play in the environment. Only 73% of the
students mentioned trash disposal being important, and most of those featm'ed details on
recycling. Very few had knowledge of landfills, and those who mentioned landfills
confused them with open-air dumps. Similarly, 70% of the students described some type
i of air pollution, but they were very confirsed between ozone depletion, greenhouse effect,
and acid rain. They believed that aerosol cans and car pollution were their chief causes of
these problems, and they demonstrated very little understanding of the chemical causes

andresultsofthedifl‘erenttypesofairpollution.

23

24

Very few students saw pesticides (19%) and fertilizers (12%) as potential
problems, even though the pretest essay instructions specifically suggested that lawns and
gardens were included in their household. Those who did mention these chemicals feared
children and animals may eat the chemicals and get sick, or it may get into the
grormdwater and hurt humans. No one mentioned the concept of run-off and how it
could damage aquatic ecosystems. On a brighter note, they were very focused on sewage
disposal and treatment, and most ofthem had a fairly good concept on what happens to
water wastes from the house.

Because of this lack of knowledge, one would expect these students to do poorly
on an open ended essay pretest, and they did. While using the same grading rubric which I
used to evaluate their posttest essay, the average scores for the pretest was a 4/40, or
10%. The low scores resulted from a very shallow understanding of the reasons and
results of the household problems. The pretest demonstrated that this unit would be
beneficial for students.

Posttest Essay.

Students averaged a 28/40 or 71% on the content portion of the posttest. A change in
mean hour the 4% pretest to 71% is very significant. In the pretest, the student were
asked to write an essay explaining all of the ways that their house effects the environment.
The posttest asked students to write the following letter: “Your fiiend, Daisy, doesn’t
believe his household affects the environment. Convince her that it does using details and
evidence that were discussed in class”. Figure 1 shows the Scores of the students’

pretests and posttests and the difference between the pretest and the posttest is substantial.

25

Figure 1. Student seem on Essay Protect and Posttest

 

 

I?“
am

 

 

 

 

 

 

 

9:
Student
P3991

 

 

 

 

25

gusto—.52

5
10~
5
o

26

While it was surprising that so many students did not have solid backgrormd information
in the area of environmental science, it is encouraging that they have gained tlat
knowledge. The median score of 80% is a testament to their mastery. Many students were
able to demonstrate their understanding in writing. This is a important skill which is very
exciting with education’s focus on writing across the curriculum.

Points on the posttest which were most often missed concerned the effects
concrete and asphalt roads have on the environment, a topic which was covered on the
first day. Students also had some difficulty with details, such as acid rain having a pH less
than 5.6. The only other common mistake was that students assumed that the reader
knew more than should be expected. Because of this assumption, many of the students’
responses were incomplete. In general, though, the student’s mastery of the material was
demonstrated.

Short Answer Post Test.

Thestudentswerealso givenashort answerquiz(AppendixC1)attheendofthe
unitto assesstheirmastery. Thisisthemore commontypeofassessmentusedinmy
classroom. On this assessment, the average score was 69% and the median score was
76%. These scores were only slightly less than the essay scores. Students who
traditionally don’t study and have difliculty retaining information did not perform well on
this exam because there were many detailed questions on the short answer assessment.
The students needed to know details such as specific numbers related to acid-base
chemistry. The essay posttest gave them a format which they could use to explain their

ideas and be comfortable telling what they know. The short answer test limited this

27

fieedom. Specifically, the question concerning pH (See appendix B2, question 10) caused
them great difliculty. Most of the students were very successful on questions which were
focused on the lab activities themselves (1c, 2, 3, 4, 6, 7, 8), but had difficulties with
detail-oriented questions that revolved around class discussions, such as specific elements
used in fertilizer, pH scales, and definitions of types of air pollution. They did well when
asked to explain their experiences and discoveries, but not as well when asked to produce
specific factual information.

Comparison with Different Assessment.

Since this unit was completely new, there is no baseline data which can be used for
comparison in student achievement. However, some comparisons can be made to other
test information gathered from another unit: the electricity unit which was taught
immediately after this thesis unit. This unit was taught using the same pedagogical
methods as this environmental unit. The only difference was the content and the absence
of a follow-up activity that tied things together and put students in a research situation (no

trial).

Table 1. Statistical Analysis of Environmental Assessments and Electricity Test

 

 

Assessment Mean Median St. Dev.
Short Answer Test 69% 74% 10.72
Essay Test 78% 80% 8.65
Ebctricity Test 70% 75% 21.21

When looking at the differences in test scores (T able 1), it appears that

performance on both short answer tests (the electricity test was also short answer) were

28

equivalent. When analyzed by a t-test, the two tests do in fact correlate to within a 95%
confidence interval. However, while it looks like the short answer test correlates well
with the electricity short answer test, the standard deviation is twice as large for the
electricity test. That is an incredible difference, leading one to believe that most students
mastered the environmental inforrmtion, while the electricity unit had a large number of
people who did very well and an equally large number of people who didn’t. In other
words, most of the students taking the environmental assessment had an fairly good
understanding of the information (around 69% :l: 11%). I was not nearly as successful
with the electricity unit, for there were many students who scored much less than 60%

(70% :l: 21%).

Final Exam.

When looking at the retention ofinformation, the students did very well with the
seven multiple choice questions related to this unit on their final exam at the end of the
year(Figure 2). The examwas inJune, almost five months afierthe studentswere
instructed and originally assessed on the unit. The class average for the environmental part
ofthe final exam was 87%, while students scored an average of 77% on the rest ofthe
exam Using the t-test statistical model, I can say with 95% certainty that the students
performed betterontheTheexamwasinJune, almost five monthsafierthestudents were
instructed and originally assessed on the unit. The class average for the environmental part
ofthe finalexamwas 87%, while students scored anaverage of 77% ontherest ofthe

exam. Using the t-test statistical model, I can say with 95% certainty that the students

29

performedbetterontheenviromnentalportionoftheexam. 'I'hisisveryimpressive

because the environmental unit was the most distant from the final exam date.

Figure 2. Student Success on Final

 

Special Education Students’ Performance.

Since allofmyclassesare inclusionclasses, it isimportantto measurethe success
of the special education students as compared to regular education students. Statistically,
this is dificult because there is a relatively small number of special education students and
thereareusuallyafewofthese individualswho do not put forthanyefl‘ort. Thisskews
most statistical data, except for median. The results of the evaluation instruments used to
measure the special education population in my classroom when compared to the entire
class are shown in Table 2. As expected, the standard deviation for the special education
students is higher than the regular education students. The special education students also
had a lower average. This difl‘erence is significant, for it does not meet the 95%

confidence interval. Thcmdianscore,though,isverysimilarinZoutofthree ofthe

30

assessments. This leads one to believe that there are a few special education students who

did not perform well, and those skewed the data. At least halfof the special education

students performed as well as or better than average than their non-labeled peers.

Although I would like all students to be very successful, I am pleased with this result.

Table 2. Comparison of Regular Education and Special Education Scores

 

 

All Students

ASSESSMENT MEAN MEDIAN ST. DEV.
short answer test 69% 74% 10.7
essay test 78% 80% 8.7

final exam questions 87% 86% 1.16

Special Education Students

ASSESSMENT MEAN MEDIAN ST. DEV.
short answer test 62% 68% 11.4
essay test 73% 80% 9.4

m1 exam questions 76% 86% 1.82

Informal Interviews

Three months after teaching and assessing the unit, I interviewed six students. The

group consisted of three males and three females, and I was careful to choose a strong,

average, and poor student to represent each of those groups. The students were also

chosen because they were in my advisory period, so that I had access to them outside of

actual class time. Therefore, they didn’t have to spend time after or before school and I

didn’t have to use instructional time for the interviews.

31

Students were first asked to address how their house affected the environment. All
of the students recalled information about acid rain, fertilizers, pesticides, and waste
disposal. Getting students to respond with details was most diflicult, and each student
focused on different parts of the unit. Because the question was so broad, I saw students
focus on aspects of the unit which interested them the most. Most students focused on
acid rain, fertilizers and pesticides were the main focus, and students had a great variance
in their answers and depth of answers. For example, some could explain how fertilizers
can get into ponds and cause the larger animals of the pond to die, while others just knew
that the fertilizers were bad for ponds.

All of the students responded favorably to the trial’s use of inforrmtion fi'om
science class. They felt that they learned more information by having the trial fornnt,
they saw connections between environmental issues and the lawsuits concerning them, and
they thought the connections between classes rmde it easier. One student even went into
great detail on how one of the groups at her trial was poorly prepared, and that cost them
success at the trial. She thought it was very evident which side did the work and was very
satisfied when that side won.

Four out of the six students felt that people should continue to use fertilizers on
lawns, five out of six thought we should not use pesticides, and six out of six thought we
should continue to use electricity. What was very encouraging about the fertilizer and
electricity answers was that the students talked about limiting their use. They saw the
dangers involved, and felt that the dangers were worth the risk if we use the resources

wisely.

32

The last question asked of the students was “What was your favorite laboratory
experiment or demonstration?” Three students enjoyed the “Production of Acid Rain
Demo” the most, two favored “The Effects of Chemicals on Brine Shrimp”, and one felt
that the “Effect of Acid Rain on Plants” was their favorite. All three of these exercises
had dramatic results and were very visual, so the results are not surprising. I would
expect most students to rank these three as their favorites.

Informal Assessment of Trial

When watching my students present in their information in their social science
class, I was filled with a sense of pride. Students were able to organize the information
that they had gathered in my class, combine it with information which they had obtained
through independent research and further experiments, and present logical arguments. It
was easy for the instructors and students alike to see who understood their material and
who didn’t. While the students were not graded on the scientific worthiness of their
presentations, the response of their peers (the jury) provided an informal grade. If they
communicated their facts correctly and refined the other side’s testimony, they ‘passed” a
fairly diflicult task. Ifthe opponents were successfirl, they had “failed”. Of the five
chsses, the defense team won one case, the prosecutors won one, and three classes ended
with hung juries. Therefore, eight of the ten groups were able to convince their peers that

they had sound arguments (80%).

CONCLUSIONS
This unit was very successful when looking at the performance of students on the

evaluation instruments. When compared to traditional short answer testing, their average
was similar to other tests. However, the median score was much higher, and they did a
much better job retaining the information as evidenced by their success on the final exam.
Since the environmental unit used hands-on laboratory experiences, cooperative learning,
everyday applications, and other similar pedagogical techniques which are used in all of
my units, one must look at another source for the success ofthe unit. I feel that the other
source was the trial.

Students needed to know the information well enough to publicly present and
defend their statements. They could not afford to memorize information: such a
technique would result in public humiliation before their peers. This trial also caused
students to seek out alternative resources in order to better grasp the problem at hand and
defend their arguments. This solidified their knowledge of the nnterial and helped to
connect their ideas. The net result is that the trial provided the extra incentive to learn and
understand the material, not just memorize it.

Could the inclusion of an alternative assessment of knowledge, such as the trial, at
the end of each unit be successful in improving student learning? Yes, but it is very time-
consuming. I was fortunate to have another teacher who shared my students and was
willingtousemymaterialinthetrialwithinherclass. Shespentthreeweekspreparing

students for the trial and allowed them time to prepare their arguments. If I had to

33

34

perform this task, the unit would last an entire quarter of the school year, which is not
feasible. However, scaled down activities similar to this could serve the same function.
Even though many teachers try to employ everyday world applications, few assess their
students in everyday contexts. The failure to do this leads to the continuation of
misconceptions and rote memorization. If we expect our students to do well on the array
of standardized tests which they will encounter, we need to correct these student mistakes.

Thestrengthofthecontentofthermitisthatitcouldbeusedinearth, life, or
physical science. Objectives in all three areas are covered, and the emphasis can be shifted
to fit the needs of the curriculum. Ideally, it would fall under an environmental science
class, but there are few science classes which are strictly environmental science. Similarly,
these activities can be scaled up or down for difi'erent grade levels of students. Since the
topics focus on the children’s homes, it causes them to examine things that they do every
day.

When looking at the teacher’s role, this unit was very time-consuming. Grading
essays for pre and posttests and the large amount of preparation that went into preparing
the experiments long before the day they were used was very trying. Performing the
experiments in the dead of winter was also difficult. However, the use of the models was
important for the students and can be used in further discussions. Students often wonder
how we know about the atom, distant stars, and other phenomena which are not directly
observable. This unit can be used as an example of model-use when talking about such

abstract ideas. The use of models, and their limits, is a key concept for young scientists.

35

While the slant of the unit was to show students that they affect the environment in
many negative ways, I also tried to balance the negative aspects with the need for the use
of difi‘erent chemicals and hunmn activities. Most of the students felt that the demand for
electricity, fertilizer, landfills, and recycling were justified, and they also understood the
disadvantages. However, students felt that pesticides were very harmfirl to the
environment and could not justify pesticide .use. Even in the trial, the attorneys
representing the farmers chose to concentrate on fertilizers and decided to not use
pesticides because they couldn’t defend it adequately. When teaching this unit again, it
would be useful to show the effect of a pest on a plant in a control/experimental group
laboratory exercise so that students would be able to view the benefits of pesticides. Since
I spent very little time discussing the benefits of pesticides and a large amount of time
showing students the negative aspects of pesticides, the students did not support the use
of pesticides. That was my only disappointment with the unit.

As instructors, we need to present relevant information to students that will
engage them and assess them in ways that prove they understand the information.
Multiple-choice, true and firlse, and short answer tests are convenient objective
measurements of student achievement, they inadequately test true understanding. Long
essays and student interviews are insightful, but not practical for busy teachers. Projects
which cause students to use their information, especially when in front of peers, will force
students to achieve actual learning and understanding--- not just memorization. As

teachers, we need to move towards better ways of assessing our students.

BIBLIOGRAPHY

BIBLIOGRAPHY

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Allen, H., F. Splittgerber, and M. Lee Manning. Teaching and Lem’ in the Middle
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American Forest Foundation. “Make Your Own Paper.” Environmental Education
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Arhar, J. “Interdisciplinary Teaming and Social Bonding of Middle Level Schools.”
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Hollander, J. and D. Brown. “Air Pollution.” The Egg-Environment Comectign.
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APPENDICES

APPENDIX A

Appendix A1

Making a Subdivision

In Holt, many new subdivisions are being built. Farmland, grassland, and forests are
being cut down, roads are being built, and the environment is changing. There is no
doubt that people need places to live. However, how will all of this affect our
environment?

1.

2.

List three ways in which the building of subdivisions will affect our environment.

Where do we get our drinking water fiom in Holt?

. When it rains, where does the water on the lawn go?

When it rains, where does the water go when it hits the road?

. Whathappenstothegroundwaterwithallofthehousesandroadsbuiltinthe

subdivisions?

. How do the production of roads affect the temperature in an area?

. Go outside and observe the thermometers. One is above the concrete and one is

above the grass. Which one is hotter?
Was your answer to question 6 correct?

Where would you rather be on a very hot day: on a road in downtown Chicago or in
the middle of grass field? Why?

39

40

Appendix A2

What Happens in a Landfill?

1. What is a landfill?
2. What goes into a landfill?
3. What are some of the problems with landfills?

a. Obtain a 400 ml beaker.
b. Place 100 ml of dirt into the beaker.
c. Place some of the trash from your house into the beaker. Make sure you place the
trashonthe side ofthebeakersothatyoucanseethem. Yourlandfillshouldcontain(at
least):
1 plastic item
1 rubber item
1 cloth item
2 different types of food (no meat or dairy products)
1 paper item.
1 biodegradable plastic (from Mr. Hodges).
d. When you are done, cover all of the objects with dirt.
e. Pour 50 ml of water onto the dirt.
f. CoverthebeakerwithPlastic wrapandsecureitwitharubberband.

4. Which of the items do you think will break down the fastest?
5. Which ones won’t break down at all?

Keep track of the landfill’s progress in your notebook. You will observe the landfill every
Wednesday until we are ready to discuss it.

41
Appendix A3
The pH of Common Substances

Background: Students should have been introduced to the difference between acids and
bases and understand the pH scale.

Purpose: To have students equate commonly known substances with different pH
numbers. In other words, to provide students with a practical knowledge
of pH.

Activity: Draw a large pH scale on the board (1-14). Review the idea that the scale
is logarithmic and each number is different by a power often. Have the
following liquids ready on a lab table:

vinegar

baking soda and water
tap water

distilled water

soda pep

milk

armnonia

sulfuric acid

lemon juice

drain cleaner

Have difl'erent students volunteer to test a liquid with pH paper, then instruct them
to write that substance under the appropriate pH number on the board. All
students should copy the chart as it is made by their fellow students. Feel flee to
test anything the students can think will be neat.

42

Appendix A4

Production of Acid Rain (LAB DEMO)

INTRODUCTION: There are many laboratory experiments which can be done to show
the effects of acid rain. However, most involve using vinegar or dilute sulfuric acid as the
starting point. I feel that students need to see that the burning of fossil flJClS causes acid
rain. In this experiment, the burning of charcoal (coal) creates a gas which turns the
Bromothymol Blue indicator to yellow or green. This indicates that the water became
acidic. Use teacher discretion in determining how you explain WHY this happens.
Truthfirlly, most of the change is due to carbon dioxide (not sulfur dioxide or nitrogen
dioxide), but you must determine if honesty fits yorn' purpose.

WP“

99°99‘95“

PRE-DEMO QUESTIONS:

. Whatisatypeofairpollutionthatyouknowof?

Whm causes acid rain?
What does acid rain cause?

DEMONSTRATION:

A. Set up device as shown in diagram. Be careful to use a glass
funnel

. Ignite Match-lite brand charcoal (or use lighter fluid on normal charcoal).

Let charcoal burn for a minute. Discuss what the students smell (Is what you
smell pollution?)

. Turn on aspirator. Explain that the aspirator is being used to suck up the gas fiom

the charcoal.
Use tongs to move beaker with charcoal under the funnel.

. Place an identical Erlenmeyer flask, with an equal amount of Bromothymol Blue,

next to the original Erlenmeyer. This will help accentuate the color change.
In about 5 minutes, a definite color change will be visible in the Bromothymol
Blue.

Unhook aspirator before turning off waterllll

POST-DEMO QUESTIONS:

What did this demo show?

How would the gas eventually become an acid in the environment?
What was the variable group in the experiment?

What was the control group in the experiment?

What would this acid rain do to plants?

What would this acid rain do to animals?

43

Appendix A5

The Effect of Acid Rain (Sulfur Dioxide) on Plant Life
Teacher Demo

Acid rain is mainly caused by sulfiir dioxide. In class, we have already
seen that the binning of fossil fiiels causes these gases to be formed.
Furthermore, we have seen that these gases turn water into an acid (acid rain).
In this demonstration, we will see what will happen directly when sulfur dioxide
is added to a plant. Remember: we are adding concentrated sulfiir dioxide to
just one plant-not to the entire environment.

Obtain two plants (a flowering plant would work best because the efiects on the flowers
are very impressive). You will also need 2 g of Sodium Nitrite and 2 ml of 5% Sulfuric
Acid.

MAKE SURE THAT THIS EXPERIMENT IS DONE IN A HOOD OR OUTSIDE!
Place one of the plants into a large Zip-lock baggie.

Place a small beaker with 2g of sodium nitrite into the baggie as well.

Pour the acid into the small beaker and seal the baggie.

After 2 minutes, open the bag and allow the gases to disperse (for real dramatic effects
and instant kill, leave the plant in for 10 minutes.

Wash hands after handling plant, bag, etc.

Dispose ofthe bag in the trash and dump the liquids down the drain.

Questions for students:
1. Write down your observations when the sodium nitrite was added to the and sulfuric
acid. .
2. a. Was this a chemical reaction?
b. Why?

3. Observe the plant after it is removed from the bag. How is it dilfcrent from the other
plant?

. Of the two plants, which plant was the control group?

. a. Does this demonstration show what really happens with acid rain in the
environment?

b. Why or why not?

. Make a hypothesis. What do you think that the acid rain actually does to

injure the parts of a plant?

filth

Q

Appendix A6

Effect of Acid Rain on Brine Shrimp

Background: Brine shrimp are small creatures which have no backbone. This means they are called
invertebrates. In our ponds, rivers, and lakes, we have many invertebrates. These creature eat bacteria,
plants, and other small creatures. As importantly, they are food for larger animals such as fish and birds.

I.

A. Obtain 4 100ml beakers.

B. Fill each beaker with 80ml of salt water.

C. Leave beaker A alone. Place lml of vinegar into beaker B. Place 2ml of vinegar into beaker C.
Place 3ml of vinegar into beaker D.

D. Use pH paper to find out the pH of each of the beakers. Write down the pH numbers.

2. Which beaker is the control?

3. Place 2 brine shrimp into each beaker. Observe the brine shrimp every 5 minutes. Make a

chartefwhatyousee, suchas: location inbeaker(highorlow), speedofmovemargdeador
alive.

 

TIME BEAKER A BEAKER B BEAKER C BEAKER D

 

0 MINUTES

 

5 MINUTES

 

10 MINUTES

 

15 MINUTES

 

20 MINUTES

 

 

25 MINUTES

 

 

 

 

 

What did increasing the pH (more acid) do to the brine shrimp?

a. If a lake had a pH of 3, what would happen to all of the brine shrimp?
b. What would happen to the rest of the animals in the lake?

Acid rain is rain with a pH less than normal. Normal rain is acidic at a pH of 5.4. Acid rain will
cause a lake’s pH to become much less than 5.4. What could you do to make the
pH of the lake go back up to what it should be?

You can treat a lake that has become too acidic. What is a better way of fixing the problem?

Michigan lakes do not have a problem with acid rain, yet we produce as much pollution as most
states. Why don’t you think we have problems?

 

45

Your Household’s Sulfur Dioxide Production

Sulfur dioxide is the major gas which causes acid rain. Most of the sulfur dioxide in the
world is produced by large factories, with 60% of all sulfiir dioxide coming fi'om coal—
burning electrical plants. Therefore, whenever you use electricity, you are producing acid
rain.

For every hour you run an electrical device that uses one watt (a watt hour, or Wh), the
electrical plant creates .006 grams of sulfur dioxide ($02).

1. Your assignment is to go home and find out the wattage ofeach of10 difi‘erent
appliances. Air conditioners, heaters, dryers, washers, dehumidifiers, fans, freezers,
refiigerators, irons, light bulbs, ovens, microwaves, refiigerators, computers, toasters,
etc. can be used. Write these in column 1 on the back.

2. Estimate how long eachofthese things isonduringaday. (Ifyouuse thewashing
machine only on Sunday, but for 7 hours, your average use during a day would be 1
hour).

3. Multiply column “1” by column “2” to get how many Watt hours you have in a day
for each appliance. Place this number in column “3”.

4. Multiply each column “3” by .006 to get how many grams of sulfur dioxide are made
each day for each appliance. Place these numbers in column “4”.

5. Add all of the numbers in colunm four together. This is how much sulfur dioxide
those 10 items make in a day Put your answer next to the (5).

6. Multiply this number (fi'om step “5”) by 30. This is how my grams of sulfur dioxide
whichismadebyyourappliancesinamonth. Putthisnumbernextto (6)

7. Multiply the number in step “5” by 365 to get how many grams of sulfur dioxide are
made by your appliances in a year. Put this number next to (7).

8. Look at Mr. Hodges’ example of the stereo on the back worksheet.

Teacher notes:

Use this information to discuss the threat to the environment. This should be especially effective after the
acid rain demos with brine shrimp and plants. The information from the BWL which were used to make
this assignment were as follows:

The Erickson Station uses .76 lb. of coal to make one kWh of electricity.
Therefore, .35g makes 1 Wh of energy.

34.8 lb. of S0; is made/ I ton of coal
Therefore, .0174 g of S02/ 1g coal is made.

.0174g SO; x .35 g coal
1 gramcoal 1 Wh

0.006g of $02 is made when l Wh of energy is used.

Appendix A7

46

Your Household’s Sulfur Dioxide Production (page 2)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Data Chart
1 2 3 4

APPLIANCE WATTS HOURS Watt hour g sulfirr dioxide

in a day B x C D x .006 grams
Mr. H’s computer 100 W 3 hours 300 Wh 1.8g
1
2
3
4
5
6
7
8
9
l0

Total grams in a day (5):

Total grams in a month (6):

Total grams in a year (7):

 

 

 

 

Note: Information provided fiom the Lansing Board of Water and Light.

 

47

Appendix A8
LARGE-SCALE POND EUTROPHICATION DEMO

Purpose of this demo is to show the effect of run-oil” fertilizer on a pond ecosystem. We
donotwantto darnagethefish, sowewilluseanairpumpandtry notto overstress
them.

1. Which tank is the control group?
2. If the tank was a pond, where could the fertilizer come from?

3. Plants make oxygen. However, if too many plants and too much algae are growing in
the pond, the oxygen in the pond will go down eventually. Why do you think that
is?

4. a. Which pond (the one with or without fertilizer) would you want to swim in?
b. Why?

5. Some fish can’t live in water with little oxygen in it. Others can.
a. Name a type of fish in Michigan that needs clean water with lots of oxygen.
b. Name a type of fish in Michigan that doesn’t.

6. a. Ifyou know whatkindsoffishthereareinalake,canyoutcll how cleanitis?
b. Explain

7. A farmer believes that the more fertilizer he puts on his farm, the more production he
gets from the farm. What’s wrong with putting on tons of fertilizer on the plants?

8. How can fertilizer on your garden or lawn get into a pond or river?

48

Appendix A9

THE EFFECT OF FERTILIZER
ON GRASS CROPS

Two weeks ago, Mr. Hodges planted an equal amount of barley seeds into two bins. He
put equal amounts of dirt into the two bins. He then watered the seeds equally. The only
difference was that Miracle-Gm fertilizer was added to the one bin.

1. Write down at least 3 observations concerning the bins.

2. Obtain one plant from each bin. Rinse ofl‘ each plant and record the following
information in your journal.

Barley plant Miracle-Gro® NO Miracle-Gro®

 

Length
Widest width

 

 

Mass

 

 

What do your numbers prove?

What was the control group in this experiment?

If you need lots of food and you only have a small amount of land, should you use
fertilizer?

What are some problem with our experiment?

If you are a farmer and you want to make more money, should you use fertilizer?
a. What is fertilizer?

b. What is food?

9. What does fertilizer do for the plant?

10. Is fertilizer plant food? Why or why not?

9:53”

sass»

49

Appendix A10

Effect of Lawn Runoff on Brine Shrimp

Background: Brine shrimp are small creatures which have no backbone. This means they
are called invertebrates. In our ponds, rivers, and lakes, we have many invertebrates.
These creatures eat bacteria, plants, and smaller creatures. They are food for larger
animals such as fish and birds.

Insecticides are chemicals that kill insects which damage plants.
Fertilizers are chemicals which supply lawns with nitrogen, phosphorus, potassium and
other important elements and compounds. They are NOT plant food.
Herbicides are chemicals which kill plants (hopefully weeds).
1. a. Obtain 4100mlbeakers.
b. Fill each beaker with 80ml of salt water.
Using the pipette, place two brine shrimp into each beaker.
Into beaker A, place 10 drops of Miracle Grow fertilizer.
Into beaker B, place 1 drop of Sevin insecticide.
Into beaker C, place 8 drops of Weed-B-Gone herbicide.
Into beaker D, do not add anything.
Which beaka is the control group?

Frets res an

a. What do you think that the insecticide will do to brine shrimp?
b. What do you think that the fertilizer will do to the brine shrimp?
c. What do you think that the herbicide will do to the brine shrimp?

3. Observe the brine shrimp every 5 minutes. Make a drart of what you see, such as: location in beaker
(high or low), speed of movement, dead or alive.

 

TIME BEAKER A BEAKER B BEAKER C BEAKER D

 

0 MINUTES

 

SMINUTES

 

10 MINUTES

 

15 MINUTES

 

20 MINUTES

 

 

25 MINUTES

 

 

 

 

 

 

50

Appendix A10
Effect of Lawn Runoff on Brine Shrimp (cont.)

a. Which substances killed or hurt the brine shrimp?
b. Why do you think that happened?

a. When you use too much fertilizer, insecticide, or herbicide on your lawn or garden,

where does it go?
b. What could it do to invertebrates in those places?

What would happen to the fish that eat these invertebrates?

a. What is the benefit of using chemicals on your lawn and garden?
b. When looking at animals, what is the risk of using chemicals on your lawn and garden?

Was this a good experiment? Why or why not?

51

Appendix A11
Making Paper

Paper is made by chopping wood into tiny pieces, putting it into water, and making some
gooey stufl' called pulp. This pulp is then placed onto a screen, the water is removed, and
wlnt you have left is a bunch of wood fibers sticking to one another: paper. The paper is
flattened, colored, etc. and then sold to stores so you can buy it and answer lab questions
on. Remember, it is the paper makers who make you write, not the teacher.

DAY 1: Cut up 6 pieces of scrap paper into 2.54cm squares (does not have to be exact).
Put the pieces into the tray with water in the back of the room. Make sure the
squares are separate.

DAY 2: Take your squares out and bring them to the blender. Alter blending, we will put

them back into your beaker and you will go to your lab station and do the
following.

a. Poor the paper pulp into your tray. Stir the paper evenly.
b. Placethe screenunderthepaperandmakesm'ethatthepaperpulpis

evenly spread above the screen.
c. Lift the screen up. Gently shake the screen back and forth for about 5
minutes. Rub a sponge underneath the screen to remove extra water.
d. On a piece of newspaper, turn your screen upside down. Push on the
comersofthe screento nnke sure mostofthepulphascome ofl‘ofthe
screen.
e. Bring the piece of paper to Mr. Hodges to iron. When he is done ironing,
make sure you put your group number and hour next to your paper.

DAY 3: Trim yorn paper to be a rectangle. Turn it in to bejudged by another class.
The group with the best looking paper will be given bonus points.

Journal Questions for lab:
1. Why should we recycle paper?
2. How is the paper you made difl‘erent fi'om the recycled paper you buy in

the store?

. How is the process of making paper different fi'om recycling paper?

4. In a recycling plant, what do you think happens to the paper that gets
trimmed fiom the sides?

5. Describe, step by step, how to recycle paper. Use as few words as possible
in your steps.

6. What is the disadvantage of recycling paper?

DJ

APPENDIX B

Day 1:

Day 2:

Day 3:

Day 4:

Appendix B

Detailed Outline of Unit
Essay question “List all the ways yorn' house affects the environment”. Explain in
detail what and how your list afl‘ects the environment.” This question was my
pretest and served as a tool to gather students’ background knowledge.
a. Worksheet on “Making a Subdivision”. Most students know about the
elimination of wildlife habitat, but this worksheet forced them to think about the
effect concrete and asphalt has on temperature and ground water recharge.
b. Creation of mini-landfills: “What Happens in a Landfill?” lab. Questions one
through five are answered and discussed.
a. Thought Question to be answered by each student: What is an acid?
b. Lecture/discussion over acids and bases, pH scale.
c. “The pH of Common Substances”. Demonstration of pH of common
chemicals and household substances using pH paper. The students were able to
place substances on the pH table and get a real sense of the differences between
materials.
a. Introduction to Bromothymol Blue as an acid/base indicator (using vinegar and
sodium hydroxide to show the color changes).
b. Demonstration “Production of Acid Rain”. This demonstrated that the burning

of coal does produce acidic gases.

52

Day 5:

Day 6:

Day 7:

Day 8:

53

c. Demonstration “The Efiect of Acid Rain on Plant Life”. This demonstrated
that sulfur dioxide directly injures plants. Discussion centered on whether or not
this was a truly accurate representation of acid rain.

“Effect of Acid Rain on Brine Shrimp” Experiment. This experiment showed that
brine shrimp cannot survive an acidic habitat. Discussion centered on how the
brine shrimp represented invertebrates in a freshwater environment, and the lost of
those invertebrates would destroy the food chain.

a. Finish discussion of acid rain. Present list of how pH damages different
creatures (Harte, 1992), (O’Neill, 1985), and effects of acid rain production on
crops and costs (Treshow, 1989), (Winner, etal.1985),

b. Class activity: Creation of a concept map linking the acid rain ideas.

c. Homework assignment: “Your Household’s Sulfur Dioxide Production”.
Student were given instructions on how to find the Watts of different appliances
and shown how to do the math to calculate sulfur dioxide production.

a. Collect and discuss homework. Discuss why sonre student’s sulfur

dioxide production was much greater than others.

b. Examination of two experiments: “Large-scale Pond Eutrophication Demo”
and “The Efi‘ect of Fertilizer on Grass Crops”. These two experiments had been
nmning for four weeks. Students were to collect data and analyze the results.

a. Discussion of the previous days two labs. Focus of the pond eutrophication

emeriment was on the effects of rapid plant growth on the pond.

54

b. “Effect of Lawn Runofi on Brine Shrimp” lab. Students saw how pesticides,
herbicides, and fertilizer affected brine shrimp.
Day 9: a. Discuss the “Effect of Lawn Runoff on Brine Shrimp” lab. Focus on pesticides
not necessarily killing fish, but killing invertebrates and depriving the fish of food
(food chain).
b. Read and discuss article “Making Your Yard Less Toxic” (Barash, 1990).
c. Look at landfills, finish questions and discussion for “What Happens in a
Landfill” lab.
(I. Shred paper and soak it in preparation for “Making Paper” lab.
Day 10: Perform “Making Paper” lab.
Day 11: a. Discuss benefits and disadvantages of recycling and go over lab questions for
“Making paper lab.
b. Trim up recycled paper.
c. Review for exams: Discuss all of the aspects of how the students’ homes affect
the enviromnent. Present students with graphic organizers which can aid in
organizing their essay.
Day 12: Short Answer Test
Day 13: Essay Test: “Your fiiend, Daisy, doesn’t believe his household affects the
environment. Convince her that it does using details and evidence that were

discussed in class”. An example of a student’s essay is in appendix C2.

APPENDIX C

Appendix C1
Short Answer Posttest Over
Your Household’s Effect on the Environment

1. a. What is fertilizer?
b. What is food?
c. Describe in detail what fertilizer will do to a pond.
(1. Name two of the three elements which are in plant fertilizers.

2. Give one reason why pesticides should be used and one reason why they
shouldn’t.

3. Explain how acid rain can
a. damage plants.
b. damage animals besides invertebrates.
c. damage a limestone statue.

4. Explain in detail how acid rain is made by Consumers Power.

5. a. What is the substance that keeps Michigan Lower Peninsula Lakes
from having trouble with acid rain?

b.

How does it work?

c. Whyisitthere?

6. Explain how your lawn fertilizer can get into a pond.

7. a. Drawalandfill.

b.
c.

.0

10.

9"!”

as 9'!»

What are the two advantages of a landfill?
What are two negatives of a landfill?

What are two advantages of recycling paper?
What are two disadvantages to recycling paper?

What are the gases responsible for acid rain?
What is the main gas responsible for the greenhouse effect?
What is the main gas which hurts the ozone layer?

AsubstancewithapHofSisa
AsubstancewithapHof3isa
HowrmnytimesmorestrongisthesubstancewithapHof3?

 

 

. IfyouaddasubstancewithapHofStoanequalamountofsubstancewitha

pHof9,thepHoftheresultwillbe:

 

55

56

Appendix C2
Sample of Student Posttest Essay

Dear Daisy,

It’s been a while hasn’t it? I got your letter. Don’t think your house does stufi' to
the environment? You have another thing coming missy. In fact I attend to prove you
wrong by using details and evidence. Still with me? Read on.

Did you turn off your light in the basement before going to bed last night? No,
huh? You know what your electric bill is? Whoa! I don’t think you need to use that
much electricity. By the way, do you know how they make your electicity? Chances are
they burn coal. So what!? Do you know what burning coal makes? Sulfur dioxide and
nitrogen oxides! Of course their bad for the environment. After the coal is burned, the
smokestacks from the plants carry them away. Where do they go? Clouds. So guess
what happens when it rains? You got it. The gases come down in precipitation. You
know what the pH is of that rain? Less than 5.4 probably. So you know what we got?
Bingo. Acid rain. And what does it do? Well, plants take in water through their
stomata. These are tiny holes on the leaves. The planct can’t use acid rain, though. So it
damages their stomata. The plant can literally not breath. And invertebrates also suffer.
Inverts can’t live with acidic waters. So when the water is too acidic. They all die. So
what, you hate flies and misquitos? Well you might, but larger animals don’t. They eat
these inverts. And bigger animals eat these and bigger animals eat these. Know wlmt I’m
getting at? The food chain. When one thing dies, the whole chain is screwed up. Guess
who’s at the end? We’re pretty close. Get what I’m saying? Besides, acid rain does
other things. That new corvette you bought is hot. You want it to stay that way? Guess
wlmt acid rain does? It wears the paint right 011". 40 grand down the tube. You fish,
right? For trout, huh? We’ll they can’t spawn in water more acidic than 5.5. Canada has
lost 10,000 lakes to acid rain. Got any aerosol cans? Get rid of all of them. Most
contain CF C’s which deplete the ozone layer. Good start?

Do you fertilize and pesticide your lawn? I thought so. Don’t you know the
dangers of pesticides? Ever heard of Blue baby syndrome? Let’s just say its not very
pretty. It happens because of fertilizers. Pesticides also kill invertebrates. After a raining.
All the stuff on your lawn goes into storm drains. They carry it to lakes and rivers. The
inverts die and once again there goes the food chain. With fertilizers it starts out the
same. It rains one night. It all goes to storm drains. They carry it to lakes/rivers. Except
nothing dies--yet. The fertilizers make the plants flourish. They grow and grow. They
produce lots of oxygen. Except sooner or hater, these plants must die. So they do and
sink to the bottom. 80 what? Decomposers then work on them or decompose them. The
plants turn to organic material Mean while, the decomposers use up all the oxygen
already produced. The fish can’t breath. They all die. After a long time, the previous

57

water way turns into a marsh, and then a swamp, and a forest. We call this , the process
of succession. Or the life of a lake/river. Cookin’, huh?

Your building of your house directly affects the enviromnent. Natural areas
probably were developed for it to be built. How do you get water? Through the ground.
Ground water. When you use it up, you start start to sink into the ground. And when you
make roads, the temperature rises up in your area. Turn off the air conditioner while your
at it. It uses carbon dioxide which creates global warming. I hope you recycle paper.
44% of landfills are paper.

Well Daisy, I hope you learned something out of all this. The earth takes care of
you. So you better start taking care ofthe earth.

Environmentally yours,
Student’s name.

nrcnran STATE UNIV. LIBRARIES
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