Human Impacts—Biodegradable Materials

Summary: How long does it take materials to break down in the environment? Students investigate whether all substances break down in the environment, and how long it takes various substances to biodegrade. They then apply this knowledge to explain what happens to wastes that end up in landfills, waterways, and the ocean.

Concepts to teach: Biodegradable, decompose

Goals: Students develop an inquiry to discover what types of materials decompose, how long it takes, and what this means for certain types of garbage that makes its way into the environment.

S3.3S.1, S3.3S.2, S3.3S.3
S4.3S.1, S4.3S.2, S4.3S.3
S5.3S.1, S5.3S.2, S5.3S.3

Specific Objectives:

  1. Differentiate between the kinds of material that nature recycles and those it does not.
    Conduct an experiment to answer an inquiry question.
  2. Recommend packaging materials based on their biodegradability.

Activity Links and Resources:

  • What is Biodegradable?—In this inquiry lesson adapted from the Alaska Activities Handbook, students conduct an experiment to determine which materials decompose when buried. Includes data worksheets.
  • What Kind of Trash Bag Breaks Down Fastest?—In this inquiry lesson excerpted from “The Complete Idiot’s Guide to Science Fair Projects”, students conduct an experiment to determine which bag materials decompose in a simulated landfill over a four-week period.


  • Have students report their data and findings from their inquiry study.
  • List pros and cons of various packaging materials.
  • Suggest ways to reduce the amount of persistent plastics in the environment.