In this lesson, students review the concept that materials in everyday products come from many different renewable and nonrenewable sources and can be classified as "biotic" or "abiotic." They watch an animated video about the materials in a juice box, then discuss the biotic and abiotic materials found in a common object. Students then create a biodegradation timeline on the floor, gaining a deeper understanding of how long different materials last. Finally, watching an animated video about garbage leads students to discuss how changes in their own behavior can reduce waste and pollution.
This lesson can stand alone or follow the companion lesson, Product Life Cycle. (See note in "Before the Lesson.")
- Identify basic components in an everyday product
- Classify materials as biotic and abiotic
- Identify disposal options for each material in the product: composting or reusing/recycling
Grade Level: 3–4
- One class period (45 minutes)
- Roll of masking tape
- Marker for labeling timeline
- Juice box for steps 3 and 4
- 10 items of various materials, both biotic and abiotic, such as a plastic bottle, a glass bottle, an aluminum can, a cotton sock, an orange peel, etc. See the Appendix (PDF) to help choose objects of different life spans.
Before the Lesson
This lesson can stand alone or follow the companion lesson, Product Life Cycle. If the lesson is to stand alone, students should first be taught the concepts of biotic and abiotic materials. Biotic materials were once alive; they include wood, paper, cotton, and wool. These materials can biodegrade (decompose). Insects and other decomposing organisms can turn these materials back into basic elements (carbon, nitrogen) that other living things can use as food and nutrients. Abiotic materials were never alive; they include metals, glass, minerals, and plastics. These materials cannot biodegrade. They can break into very small pieces, but they cannot be used as food by living organisms. Note: Crude oil is technically biotic (it is the decayed remains of plants and animals); however, processing affects the chemical structure and renders the plastic made from it resistant to decay.
Before class, use masking tape to create a timeline on the floor. Label one end "Now," and mark off 50-year intervals every three feet, for a total span of 500 years.
1. (Estimated time, steps 1–5: 10 minutes) Tell students that they are going to watch a video about a secret weapon. They are going to try to guess the weapon before the character in the video does.
2. Show the Juice Boxes Video. While viewing, pause the video just before the juice box is revealed. Ask students to guess what the weapon is. Then play the rest of the video. Were students surprised by the "secret weapon"?
3. Hold up the juice box, or pass it around the class. Ask students, What is a juice box made of? Are each of these materials biotic or abiotic? Write responses on the board. Note that students may not know much of the information. If this is the case, ask, Why don't we know this information?
4. Point out that a juice box is made of both biotic and abiotic materials. Ask students to explain how this affects how long the juice box will be in the landfill. (Some materials, like paper, decompose quickly, but it could take much longer for a juice box because it's coated in plastic.)
5. Transition to the biodegradation timeline by saying, Let's explore biodegradation further.
6. (Estimated time, steps 6–9: 15 minutes) Assemble students around the biodegradation timeline. Help students connect the ages on the timeline to things they know. Ask, Do you know anyone who's 50 years old? How about 100 years old? How old is the oldest building in town?
7. Pass out 10 items made of varied materials, both biotic and abiotic, such as a plastic bottle, glass bottle, aluminum can, cotton sock, orange peel, etc. Choose one as an example, and help students place it on the timeline to show how many years it will take to biodegrade or break into pieces in a landfill. Ask students to put the rest of the items on the timeline themselves. Reinforce the point that some materials, like glass and plastic, will eventually break into tiny pieces but won't biodegrade. (Optional: set up two timelines with two sets of items on opposite sides of the room.)
8. When students have finished placing the items on the timeline, reveal the answers and have students rearrange the items, as needed. (See Appendix: Decomposition of Litter for answers.)
9. Use the timeline as an opportunity to emphasize that abiotic materials, such as tin foil or glass, will never decompose.
10. (Estimated time, steps 10–12: 15 minutes) Now tell students that they are going to watch a video about a boy named Oliver and a big pile of garbage. Tell them to watch for biotic and abiotic items in Oliver's garbage pile.
11. Show the Garbage Video. After watching the video, discuss the following questions:
- What are better options for Oliver—or anyone—to dispose of their trash?
- What should Oliver do differently in the future?
12. (Estimated time, step 13: 5 minutes) Conclusion: Ask students to share a story about recycling, reusing, or composting. The story could be about something they've done or plan to do, or about what someone else had done.
Check for Understanding
Ask students to label things around the classroom as biotic, abiotic, or mixed. Can they identify the best disposal option for different items, based on this knowledge?
Appendix: Decomposition of Litter
You can also view a printable version of the Appendix (PDF).
- Banana: 3–5 weeks
- Batteries: 100 years
- Cardboard box: 4 weeks
- Cigarette butt: up to 10 years
- Cotton rag: 1–5 months
- Disposable diapers: 500–600 years
- Glass bottle: unknown (will eventually break into tiny bits but not biodegrade)
- Leather: up to 50 years
- Lumber: 10–15 years
- Milk cartons (plastic-coated): 5 years
- Monofilament fishing line: 800 years
- Nylon fabric: 30–40 years
- Orange peel: 2–5 weeks
- Paper: 2–5 months
- Plastic 6-pack rings: 450 years (in this time, it will break into tiny bits but not biodegrade)
- Plastic bag: up to 500 years (in this time, it will break into tiny bits but not biodegrade)
- Plastic-coated paper: 5 years
- Plastic soda bottles: unknown (will eventually break into tiny bits but not biodegrade)
- Rope: 3–14 months
- Rubber boot sole: 50–80 years
- Soda can: 200–500 years
- Tin foil: never (will eventually break into tiny bits but not biodegrade)
- Wool clothing: 1–5 years
Lesson developed in collaboration with Creative Change Educational Solutions.