By analyzing the contents of a bag of trash, students will be able to identify the natural resources used to produce a product and whether those resources are renewable or nonrenewable.
CA State Standards
Sources of energy and materials differ in amounts, distribution, usefulness, and the time required for their formation.
As a basis for understanding this concept:
- Students know the different natural energy and material resources including air, soil, rocks, minerals, petroleum, fresh water, wildlife, and forests, and know how to classify them as renewable or nonrenewable.
- Students know the natural origin of the materials used to make common objects.
The students will demonstrate an ability to:
- Identify the natural resources from which products are made.
- Distinguish between renewable and nonrenewable resources.
- Identify responsible choices and uses of products that help conserve our natural resources.
One bag of trash, yarn, signs for natural resource groups, Class Inventory Sheet, and Trash Classification Chart.
Part A: 1-2 hours. Part B: 2 hours.
Natural resource, renewable, nonrenewable, recycle, reuse, reduce, and biodegrade.
This lesson deals with the ultimate sources of common objects which are called natural resources. Natural resources are defined as "materials found in nature that are used by people – sunshine, water, air soil, minerals, forests, and wildlife."
Students do not often consider or even know the natural sources of commonly used goods. They must be reminded that manufactured items do not appear magically and that the ultimate cost of acquiring the objects we rely on goes far beyond the monetary price we pay for them. Objects that humans use typically come from four main natural resource groups: forests/plants, animals, minerals, and fossil fuels.
Students can inventory the objects in their classroom. Then, they can trace them back to the natural materials from which they were manufactured, and classify the materials as renewable or nonrenewable. Renewable resources have the capacity to replenish themselves within a human lifespan. Nonrenewable resources do not replenish themselves within a human lifespan. Trees or plants are examples of renewable resources since they can be grown within our lifetimes.
What humans do with objects once they are finished with them can have a huge impact on our environment and our lives. Responsible consumers attempt to reuse items as often as possible, for example, using both sides of a piece of paper, washing and reusing plastic ware, etc. Often objects are suitable for recycling, such as glass, aluminum, certain plastics, etc. Reusing or recycling products conserves natural resources. When items can't be reused or recycled, it is very advantageous if the item will biodegrade and become part of the soil and environment. When objects biodegrade, they don't take up space in our already over-taxed landfills. Certain items, such as banana peels, newspapers, etc., biodegrade easily. Other items, like glass, certain plastics, Styrofoam, etc., do not biodegrade easily.
If an item will not breakdown and become part of nature within a human lifetime, we do not consider it to be biodegradable. When items can't be recycled or reused and will not biodegrade, they are considered to be "true trash." True trash must be kept in landfills or disposal sites for many generations.
Several days prior to this lesson, bring in one large (empty) trash bag. Ask the students to each bring one piece of trash to help fill up the bag. (Give students guidelines on what not to bring – broken glass, unsafe items, etc.) When the bag is full, place it in front of the class and read the following statistic: The American people throw away approximately 10 billion bags of trash each year. This is enough trash to cover a 4-lane highway, six feet deep in trash, from California to New York.
Part A: In this part of the lesson, students will understand that all objects come from natural resources. Some natural resources are renewable and some are not.
- Hold up the bag of trash and ask the class, "Does everything in this bag come from nature?" Define "natural resources" with the class.
- Make four large circles with yarn or string. Label each circle with the name of a natural resource group – forests/plants, minerals, animals, and fossil fuels. Pull out individual items and place the trash items in one of the groups according to the main natural resource from which the item came
Natural Resource Examples of Items Forests/plants Paper, pencil, cotton rag Animal Leather shoe, wool sock Mineral Aluminum can, glass Fossil Fuel Plastic wrapper, nylon
- You should now have piles of trash that represent the products of different natural resources. Define renewable and nonrenewable resources (see Background for definition). Discuss which piles represent renewable resources and which piles represent nonrenewable resources. Label each group as either "renewable" or "nonrenewable." Discuss the advantages of renewable resources in terms of continued availability to humans. Have the students take an inventory of the classroom and identify and record objects from each of the four natural resource groups on the student worksheet provided.
Extension Idea: Have the students make a graph showing where most objects in the classroom come from.
Note: If possible, return the trash items to the plastic trash bag and save these items for Part B of this lesson.
Part B: In this part of the lesson, students will be analyzing individual items of trash to classify them according to possible uses or outcomes (see Trash Classification Chart).
Make an overhead transparency of the Trash Classification Chart, or hand out individual photocopies of the chart. Explain that objects we use have four possible outcomes: recycle, reuse, biodegrade, and true trash. Be sure students understand the meaning of the four possible outcomes (see Background for definition). Take the bag of trash from the previous lesson and remove one item at a time. Discuss each object by asking the following questions:
- Could it have been reused?
- Could it have been recycled?
- Will it biodegrade?
- Is it true trash?
- Record each item on the Trash Classification Chart.
- After all items have been recorded on the chart, discuss the following questions:
- Which natural resources produced true trash? Are these natural resources renewable or nonrenewable?
- Which natural resources did not produce true trash? Are these natural resources renewable or nonrenewable?
- Which natural resources produced items that biodegrade easily? Are these from renewable or nonrenewable natural resources?
- Which natural resources produced the most recyclable items?
- Discuss the advantages of recycling and reusing items. A: Conserves natural resources, reduces landfill and pollution, etc.
Discuss the disadvantages of true trash. A: Wastes natural resources and increases pollution and landfill sites.
How can we avoid true trash? A: Reduce! Attempt to use less or not buy products that cannot be recycled or reused.
These are known as the Three R's: Reduce, Reuse, Recycle. By reusing and recycling our products and by reducing our use of all products, we can help conserve our natural resources.
- Use the Trash Dilemma Cards to help students identify ways in which they can start using the Three R's.
- Read Sarah Cynthia Sylvia Stout Would Not Take the Garbage Out by Shel Silverstein. Have students classify the objects in this poem on the Trash Classification Chart.
- Read 50 Simple Things You Can Do To Save the Earth.
- Learn the Conservation Pledge. Make up your own pledge of something special you will do to help conserve natural resources.
- Start a recycling program at your home, classroom, or school.
- From your city or county, invite an expert on waste management or recycling to make a presentation to your students.
- Have students develop creative ways to handle our future trash.
The Three R's comes from the SCICON Instructional Guide.
Trash Dilemma Cards
These hypothetical situations can be used for small group or class discussions.
- You are thirsty and enter a mini-market to buy a soft drink. Your favorite brand is only offered in a non-returnable and non-recyclable container. What will you do?
- Buy your favorite brand.
- Buy another brand in a recyclable container.
- Walk to another store.
- Talk to the store manager about ordering drinks in recyclable containers.
- Your parents ask you to help clean the garage. There is a pile of items that your family does not want such as old tools, clothes, toys, dishes, etc. Your parents want to throw them away. What are some better suggestions that you could give them?
- You would like to put up a wild bird feeder in your backyard. There are plastic ones on sale at the pet store. You should:
- Buy the plastic one.
- Buy some wood and make your own.
- Make a wooden one out of scrap lumber.
- Make a birdfeeder out of a plastic container that you found in the trash.
- You are on a committee to plan a class picnic. For refreshments, the options mentioned are:
- Serving sodas in aluminum cans.
- Serving punch in Styrofoam cups.
- Serving punch in paper cups.
- Serving punch in washable cups.
What do you think the committee should do?
- You attend a meeting regarding the nearby landfill or dump which is nearly full. Many alternatives are suggested to alleviate the problem. What do you suggest?
- Raise the fee for a load of trash.
- Lower the fee for a load of trash.
- Create a new landfill site.
- Find a landfill site nearby that will take your town's trash.
- The city should encourage people to recycle.
- The city should pass and enforce recycling laws.
- You buy several items at a market. They offer you the choice of either a paper bag or plastic bag. You should:
- Take the paper bag.
- Take the plastic bag.
- Say, "Thank you, but I brought my own bag."
What would you do in the same situation if you bought only one item?
An additional worksheet for "The Three R's" is available for download in pdf format.
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