TRASH OR TREASURE?
(Training Powerpoint Available)
Students will work in teams to play a game learning about the length of time it takes various materials to
decompose.
OBJECTIVES
The student will be able to
 Describe the difference between biodegradable and non-biodegradable materials.
 Name materials that could be recycled rather than buried in a landfill.
VOCABULARY
 Biodegradable: Waste that is capable of being broken down into basic chemical components by
biological agents, especially bacteria
 Non-biodegradable: Waste that cannot be broken down in the environment by natural process
 Compost: A mixture of decaying organic matter, as from leaves and manure, used to improve soil
structure and provide nutrients
 Decompose – To break down into components or basic elements
 Landfill: a place to dispose of garbage, rubbish, etc. by burying it under soil or earth
MATERIALS/EQUIPMENT
 Multiple sets of pictures for the game (Appendix C)
 Cards labeled A, B, C - one set for each group (Appendix D)
 Small whiteboards and markers – one per team
TIME NEEDED: 30-40 minutes depending on whether or not you use all of the rounds
DEGREE OF PHYSICAL ACTIVITY: low
RUNNING THE ACTIVITY
Show students a trashcan/waste basket. Have them name things that we typically throw away. Discuss
where those things go once they leave our homes and schools. Talk about landfills and how they work.
(An explanation and diagram are included in Appendix A.)
Ask the students if everything that gets thrown out is really no longer useful - can some things be used in
other ways? Talk with the students about recycling, asking about what things students recycle at home or
at school. Then talk about composting – how we can collect certain foods and plant materials and let
them decompose into soil. If your site does composting, remind your students of how exactly it is done at
this location (e.g. collecting food at meals, where foods scraps are taken, etc.)
Point out that some things that end up in landfills may start to break down – decompose. They do this
because microorganisms in the soil that is used to cover materials in a landfill begin to interact and start
to break down the materials. Introduce the term “biodegradable.” Explain that biodegradable materials
left in landfills – whether or not they are recyclable or compostable – will break down – some quickly,
others taking many years. Then ask the students what term we use to mean materials that cannot be
broken down through natural processes. (“non-biodegradable”)
Explain that today students will play a game to test their understanding of how long materials will last in a
landfill. Show students the game cards. Explain that they will be asked questions about recycling and
decomposition and will give their answers by holding up either picture cards or letter cards. Correct
answers earn the teams points.
Depending on the group, you may want to take a time at the start of the game to discuss the fact that
there are variations in how long scientists think it will take for some materials to decompose. Sometimes,
sources disagree on exactly how long it will take because decomposition depends on factors like the
amount of sunlight, moisture, and air exposure. If the materials are tightly packed and covered,
decomposition will take much longer. Sometimes, the materials will break down into smaller and smaller
pieces, but it will never really go away. If students question the values, use this as a teachable moment.
Talk about the challenges of knowing the long-term consequences of using materials we’ve created, like
plastics or styrofoam since they’ve only been used for a relatively short time. Scientists and engineers
make educated guesses for decomposition rates based on their understanding of the chemical structure
of the materials and how they will interact with chemicals found naturally in the environment and
chemicals we introduce. For this game, the times given for the decomposition rates are averages.
Divide the class into several groups and position them around the room. Have chaperones sit with the
groups – they can be responsible for keeping scores. Pass out one set of picture cards and a set of letter
cards (for multiple choice questions) to each group. Give them a few minutes to familiarize themselves
with the cards and to ask questions about any images with which they may be unfamiliar.
The Game
First Round: Have each team to look at their pictures and choose the three things that will take the
shortest amount of time to decompose if left our in the open. Groups score 10 points for each correct
answer. Correct answers include facial tissue (1-2 weeks), paper towels (2-4 weeks), banana peels (1
month), and
newspaper (6 weeks).
Second Round: Have each team to look at their pictures/objects and choose the three things that will
take the longest amount of time to decompose if left out in the open. Groups score 10 points for each
correct answer. Correct answers include electronics (millions of years), glass (1-2 million years), tinfoil
(unsure/never?), styrofoam (unsure/never?)
Third Round: Show the groups the pictures of the milk carton and the plastic milk jug. Tell them one will
decompose in 5 years and the other will take about 500 years to decompose. Have them choose the
picture of the one that will decompose first (in 5 years) from their set of pictures. On the count of three,
the groups should hold up their choice. Groups score 10 points for the correct answer: milk cartons.
Fourth Round: Show the groups the tin can and the aluminum can. Explain that one will decompose in
50 – 100 years while the other one may never decompose – scientists aren’t sure how long it will take.
Choose the picture of the one that will decompose first (in 50-100 years). On the count of three, the
groups should hold up their choice. Groups score 10 points for the correct answer: tin cans.
Fifth Round: Tell students they will need their letter cards: A, B, C. Show the groups the picture of the
disposable diaper. Explain that they are called disposable, meaning you can throw them away instead of
having to wash them like you do with cloth diapers. So how long will it take a diaper to decompose?
a) 2 – 5 years
b) 20-50 years
c) 200- 500 years
On the count of three, each group should hold up their letter choice card: A, B, or C. The correct answer
is C (200-500 years). Correct answers earn the groups 10 points.
Sixth Round: (Worth 20 points.) Have the groups look through their pictures and find the wool socks,
leaves, lumber, and apple core. They need to order the pictures from left to right, in the order in which
they will decompose. Give the groups 1-2 minutes to make their choices. Call “time” and check each
group’s order. The correct order is apple core (2 months), leaves (6 months), wool socks (1-2 years), and
lumber (10-15 years).
Seventh Round: Show the groups the pictures of the stack of paper and the cardboard boxes. Tell them
one will decompose in 2 months and the other will decompose in about 5 months. Have them choose the
picture of the one they think will decompose first (in 2 months) from their set of pictures. On the count of
three, the group should hold up their choice. Groups score 10 points for the correct answer: cardboard.
Eighth Round: (Worth 20 points) Have the students find the pictures of cigarette butts, orange peel,
monofilament fishing line, and batteries. They need to order the pictures from left to right, in the order in
which they will decompose. Give the groups 1-2 minutes to make their choices. Call “time” and check
each group’s order. The correct order is orange peel (6 months), cigarette butts (2-5 years),
batteries (100 years), and monofilament fishing line (600-800 years).
Ninth Round: Tell students they will need their letter cards: A, B, C. Show the groups the picture of the
plastic bottles. How long does it take a plastic bottle to decompose?
a) 10 - 15 years
b) 45 -100 years
c) 450 – 1000 years
On the count of three, each should hold up their letter choice card: A, B, or C. The correct answer is
C (450-1000 years). Correct answers are worth 20 points.
Tenth Round: (Worth 25 points) From all the pictures/objects that you have, pick out four things that you
could be composted. Acceptable answers will include: banana peel, apple core, orange peel, paper,
leaves, newspaper, paper towels, cardboard.
Eleventh Round: (Worth 25 points) From all the pictures/objects that you have, pick out four things that
you could recycle. Acceptable answers will include: electronics, milk jugs, glass, aluminum can, tin can,
newspaper, cardboard, tin foil, plastic bottles.
Tally up the points to see which team scored the most. Ask everyone to look at the pictures one more
time and choose one that they learned something interesting about. Call on students to share the fact
they found interesting.
Wrap-Up
Either in journals or through class discussion, have the students address the following questions:
1. What surprised you about the amount of time needed for things to decompose?
2. What was one thing you learned today?
3. How can you use the thing you learned today to make a change in your life?
WAYS TO USE/INTEGRATE THIS ACTIVITY
Combine with Resources: How Long Will They Last?
Use as an evening program.
STEM CONNECTIONS
Science: Students will need to predict and classify.
Math: Students will need to estimate.
Students will also need to use teamwork and problem-solving skills.
SOURCE(S)
Modeled on Long Lake Conservation Center’s Dumpster Diving activity
APPENDIX A: How a Landfill Works (from the NIE supplement titled “Talkin’ Trash”)
Once a garbage truck is full of trash, it heads to the sanitary landfill to dump its load, then heads back out to the
neighborhoods to pick up more.
To flatten and crush the many loads of garbage, a compactor — a large bulldozer with giant spikes on its wheels —
is driven back and forth over it. Trucks then level it out and pack it down.
A layer of dirt is spread over the newly flattened garbage by machines called graders. The trash is covered with dirt
as soon as possible to help keep odors down, stop the spread of bacteria, and discourage scavengers such as
gulls, rats, and insects.
As rainwater passes through the layers of trash, it becomes polluted with household hazardous waste like bug
sprays, paints, household cleaners, and car oil. This polluted water is called leachate. Before sanitary landfills were
built, leachate would collect underneath the many layers of garbage and slowly leak out into the ground, eventually
making it into water supplies. Modern landfills are lined with layers of gravel, clay, and plastic to keep that from
happening. Leachate is now collected and piped into treatment facilities.
Rotting organic garbage produces a gas called methane, which is the primary
ingredient in the kind of gas that is used for creating electricity or for heating
and cooking in homes. In landfills, where huge masses of garbage are
decomposing in an enclosed area, there is a danger of methane fires or
even explosions. Sanitary landfills are equipped with pipes that bring the
methane to the surface, then into treatment plants where it can be turned
into electricity and sold.
What happens when a landfill is full? It is capped, or closed off, with a layer
of clay followed by a 6-foot layer of earth. Capped landfills are then
“reclaimed.” Some have become parks, others parking lots, and still others
have served as the foundations to airports.
APPENDIX B: Table of Materials and Typical Amount of Time Needed to Decompose
Knowing for sure how it will take something to decompose isn’t a certainty. Materials buried in landfills
will definitely take longer to decompose (some people predict 10-20 times longer) because of lack of
exposure to air, water, and bacteria that can react with the objects.
Things made from materials like glass and aluminum may never decompose because they aren’t
affected by air, water, or bacteria. Their resistance to decomposition is what makes them so useful for
storage. If exposed to the correct chemicals, aluminum will react and begin to break down, but those
chemicals aren’t ones typically found in landfills, so aluminum may last forever.
Other materials will break down, but never completely. Some plastics just break down into smaller and
smaller pieces, but never disappear.
Sources:
http://www.recycling-revolution.com/recycling-facts.html
http://www.thatdanny.com/2008/06/06/how-long-does-it-take-a-plastic-bag-or-a-glass-bottle-to-decompose/
U.S. National Park Service; Mote Marine Lab; New Hampshire Department of Environmental Services
Item
Aluminum can
Apple core
Banana peel
Batteries
Cardboard boxes
Cigarette butts
Disposable diaper
Cotton rag
Electronic devices
Facial tissue
Glass
Leather boot
Leaves
Lumber
Milk carton
Milk jug (plastic)
Monofilament fishing line
Newspaper
Paper
Paper towel
Plastic bottles
Plastic six-pack ring
Orange peel
Styrofoam cups
Tin can
Wool sock
How long
decomposition takes
(on average)
unknown; forever?
2 months
2-5 weeks
100 years
2 months
2-5 years
250-500 years
5 months
Millions of years
1-2 weeks
unknown; forever?
40-50 years
6 months
10-15 years
5 years
500 years
600-800 years
6 weeks
2-5 months
2-4 weeks
450 years; never?
450 years; never?
6 months
unknown; forever?
50-100 years
1-5 years
APPENDIX C: Picture Cards for Game
Aluminum Foil
Batteries
Styrofoam Cups
Paper
Electronic Devices
Cigarette Butts
Glass Jars
Facial Tissue
Milk Carton
Newspaper
Lumber
Orange Peel
Apple Core
Banana Peel
Aluminum Cans
Cardboard Boxes
Plastic Bottles
Disposable Diapers
Monofilament
Fishing Line
Tin Can
Paper Towels
Wool Socks
Leaves
Milk Jugs
APPENDIX D: ABC Choice Cards
ABC
APPENDIX E: Question Cards
First Round (worth 10 points for each correct answer))
Look at your pictures and choose the three things that will take the
shortest amount of time to decompose. Groups will score 10 points
for each correct answer.
Correct answers include facial tissue (1-2 weeks),
paper towels (2-4 weeks), banana peels (1 month), and
newspaper (6 weeks).
Second Round (worth 10 points for each correct answer))
Look at your pictures and choose the three things that will take the
longest amount of time to decompose. Groups score 10 points for
each correct answer.
Correct answers include electronics (millions of years),
glass (unknown; forever?), tinfoil (unknown; forever?),
styrofoam (unknown; forever?)
Fourth Round (worth 10 points)
Look at the pictures of the tin can and the aluminum can. One will
decompose in 50 – 100 years while the other one may never
decompose – scientists aren’t sure how long it will take. Choose
the picture of the one that will decompose first (in 50-100 years).
On the count of three, hold up your choice.
Groups score 10 points for the correct answer: tin cans.
Fifth Round (worth 10 points)
You will need your letter cards: A, B, C. Look at the picture of the
disposable diaper. They are called disposable, meaning you can
throw them away instead of having to wash them like you do with
cloth diapers. So, how long will it take a diaper to decompose?
a) 2 – 5 years
b) 20-50 years
c) 200- 500 years
On the count of three, hold up the letter of your choice card. A
correct answer earns the group 10 points.
The correct answer is C (200-500 years).
Third Round (worth 10 points)
Look at the pictures of the milk carton and the plastic milk jug. One
will decompose in 5 years and the other will take about 500 years
to decompose. Choose the picture of the one that will decompose
first (in 5 years) from your set of pictures. On the count of three,
hold up your choice.
Sixth Round (worth 20 points)
Look through your pictures and find the wool socks, leaves,
lumber, and apple core. Order the pictures, from left to right, in the
order in which they will decompose. You will have 2 minutes to
make your choices. A correct answer is worth 20 points.
The correct order is apple core (2 months), leaves (6 months),
wool socks (1-2 years), and lumber (10-15 years).
Groups score 10 points for the correct answer: milk cartons.
Seventh Round (worth 10 points)
Look at the pictures of the stack of paper and the cardboard boxes.
One of these items will decompose in 2 months and the other will
decompose in about 5 months. Choose the picture of the one your
group thinks will decompose first (in 2 months). On the count of
three, hold up your choice.
Groups score 10 points for the correct answer: cardboard.
Eighth Round (worth 20 points)
Find the pictures of cigarette butts, orange peel, monofilament
fishing line, and batteries. Order the pictures from left to right, in
the order in which they will decompose. You will have 2 minutes to
make your choices.
Call “time” and check each group’s order. The correct order is
orange peel (6 months), cigarette butts (2-5 years),
batteries (100 years), and
monofilament fishing line (600-800 years).
Ninth Round (worth 20 points)
You will need the letter cards: A, B, C.
Look at the picture of the plastic bottles. How long does it take a
plastic bottle to decompose?
a) 10 - 15 years
b) 45 -100 years
c) 450 – 1000 years
A correct answer is worth 20 points.
On the count of three, hold up your answer card.
The correct answer is C (450-1000 years).
Tenth Round (worth 25 points)
From all the pictures/objects that you have, pick out four things that
could be composted. You will have 2 minutes. If all your choices
are correct, your group earns 25 points.
Acceptable answers will include: banana peel, apple core, orange
peel, paper, leaves, newspaper, paper towels, cardboard.
Eleventh Round (worth 25 points)
From all the pictures/objects that you have, pick out four things that
you could recycle. You will have 2 minutes. If all your choices are
correct, your group earns 25 points.
Acceptable answers will include: electronics, milk jugs, glass,
aluminum can, tin can, newspaper, cardboard, tin foil, plastic
bottles.
APPENDIX F: STANDARDS
Subject
Grade
Level
Code
Standards
4
4.8.1.1
Common Core Speaking
and Listening Standards
K-5
5
5.8.1.1
Common Core Speaking
and Listening Standards
K-5
Common Core Speaking
and Listening Standards
6-12
6
6.9.1.1
English
Language
Arts
K-12
(2010)
Common Core Speaking
and Listening Standards
6-12
7
7.9.1.1
Common Core Speaking
and Listening Standards
6-12
8
8.9.1.1
Benchmark
Engage effectively in a range of collaborative discussions with diverse
partners on grade 4 topics and texts, building on others’ ideas and
expressing their own clearly.
b. Follow agreed-upon rules for discussions and carry out assigned roles.
c. Pose and respond to specific questions to clarify or follow up on
information, and make comments that contribute to the discussion and link
to the remarks of others.
e. Cooperate and problem solve as appropriate for productive group
discussions.
Engage effectively in a range of collaborative discussions with diverse
partners on grade 5 topics and texts, building on others’ ideas and
expressing their own clearly.
b. Follow agreed-upon rules for discussions and carry out assigned roles.
c. Pose and respond to specific questions to clarify or follow up on
information, and make comments that contribute to the discussion and link
to the remarks of others.
e. Cooperate and problem solve as appropriate for productive group
discussions.
Engage effectively in a range of collaborative discussions with diverse
partners on grade 6 topics, texts, and issues, building on others’ ideas and
expressing their own clearly.
b. Follow rules of r collegial discussions, set specific goals and deadlines,
and define individual roles as needed.
c. Pose and respond to specific questions with elaboration and detail by
making comments that contribute to the topic, text, or issue under
discussion.
d. Review the key ideas expressed and demonstrate understanding of
multiple perspectives through reflection and paraphrasing.
e. Cooperate, mediate, and problem solve to make decisions as
appropriate for productive group discussion.
Engage effectively in a range of collaborative discussions with diverse
partners on grade 7 topics, texts, and issues, building on others’ ideas and
expressing their own clearly.
b. Follow rules of collegial discussions, set specific goals and deadlines,
and define individual roles as needed.
c. Pose questions that elicit elaboration and respond to others’ questions
and comments with relevant observations and ideas that bring the
discussion back on topic as needed.
d. Acknowledge new information expressed by others and, when
warranted, modify their own views.
e. Cooperate, mediate, and problem solve to make decisions as
appropriate for productive group discussion.
Engage effectively in a range of collaborative discussions with diverse
partners on grade 8 topics, texts, and issues, building on others’ ideas and
expressing their own clearly.
b. Follow rules of r collegial discussions, set specific goals and deadlines,
and define individual roles as needed.
c. Pose questions that elicit elaboration and respond to others’ questions
and comments with relevant observations and ideas that bring the
discussion back on topic as needed.
d. Acknowledge new information expressed by others and, when
warranted, modify their own views.
e. Cooperate, mediate, and problem solve to make decisions as
appropriate for productive group discussion.
English
Language
Arts
K-12
(2010)
Common Core Speaking
and Listening Standards
6-12
9-10
9.9.1.1.
English
Language
Arts
K-12
(2010)
Social
Studies
(2004)
Science
K-12
(2010)
Common Core Speaking
and Listening Standards
6-12
11-12
11.9.1.1
4-8
Geography
V.D.2.
4-8
Economics
VI.B.2
5
5
9-12
9-12
5.3.4.1.3
5.4.4.1.1
9.2.3.1.2
9.3.4.1.2
The student will describe
how humans influence
the environment and in
turn are influenced by it.
The student will
understand basic
principles of economic
decision-making.
In order to maintain and
improve their existence,
humans interact with and
influence Earth systems.
Humans change
environments in ways that
can be either beneficial or
harmful to themselves
and other organisms.
There are benefits, costs
and risks to different
means of generating and
using energy.
People consider potential
benefits, costs, and risks
to make decisions on how
they interact with the
natural systems.
Initiate and participate effectively in a range of collaborative discussions
with diverse partners on grades 9-10 topics, texts, and issues, including
those by and about Minnesota American Indians, building on others’ ideas
and expressing their own clearly and persuasively.
b. Work with peers to set rules for collegial discussions and decisionmaking, clear goals and deadlines, and individual roles as needed.
C. Propel conversations by posing and responding to questions that relate
the current discussion to broader themes or larger ideas; actively
incorporate others into the discussion; and clarify, verify, or challenge
ideas and conclusions.
d. Respond thoughtfully to diverse perspectives, summarize points of
agreement and disagreement, and, when warranted, qualify or justify their
won views and understanding and make new connections in light of the
evidence and reasoning presented.
Initiate and participate effectively in a range of collaborative discussions
with diverse partners on grades 11-12 topics, texts, and issues, including
those by and about Minnesota American Indians, building on others’ ideas
and expressing their own clearly and persuasively.
b. Work with peers to promote civil, democratic discussions and decisionmaking, set clear goals and deadlines, and establish individual roles as
needed.
C. Propel conversations by posing and responding to questions that probe
reasoning and evidence; ensure a hearing for a full range of positions on a
topic or issue; clarify, verify, or challenge ideas and conclusions; and
promote divergent and creative perspectives.
d. Respond thoughtfully to diverse perspectives, synthesize comments,
claims, and evidence made on all sides of an issue; resolve contradictions
when possible; and determine what additional information or research is
required to deepen the investigation or complete the task.
Students will analyze the advantages and drawbacks of several common
proposals to change the human use of environmental resources.
Students will apply a decision-making process to make informed choices
Compare the impact of individual decisions on natural systems.
Give examples of beneficial and harmful human interaction with natural
systems.
Describe the trade-offs involved when technological developments impact
the way we use energy, natural resources or synthetic materials.
Explain how human activity and natural processes are altering the
hydrosphere biosphere, lithosphere and atmosphere, including pollution,
topography and climate.