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How Long Does Trash Last?
(A Cooperative Learning Activity)

Reviving Reviews: 
                          Refreshing Ideas Students Can't Resist

Return to Five Lessons Teach Students to Reduce, Reuse, Recycle



  • Arts & Humanities:
    Language Arts
  • Arts & Humanities:
    Visual Arts
  • Educational Technology
  • Mathematics:
  • Mathematics:
  • Science: Physical Science:


  • 3-5
  • 6-8

Brief Description

Students learn how long trash lasts in landfills in this cooperative activity.


Students will
  • work together in groups to formulate their best estimate of how long some trash items might last in a landfill.
  • learn about environmental consequences of not recycling.
  • use a graph-making tool to create a graph. (Optional)


Trash, recycle, biodegrade, longevity, garbage, landfill

Materials Needed

  • aluminum can (soda pop can)
  • banana
  • cigarette butt
  • cotton rag
  • glass bottle
  • leather boot
  • paper bag
  • plastic 6-pack rings
  • plastic jug
  • rubber sole of the leather boot (above)
  • Styrofoam cup
  • tin can (soup or vegetable can)
  • wool sock
Write the above list of items on a chalkboard or chart.

Lesson Plan

Before the Lesson
Display for students the materials you have collected (see Materials section above). Provide a chart on which you have written the names of those materials.

Draw students' attention to the items you have gathered. You might ask, What do all the items have in common? If your students are too young to figure out the answer to the question, you can share with them that each of the items will likely end up in a landfill one day.

Next, ask What will happen to these items when they end up in the landfill? How long do you think they will last there? Do they disappear/disintegrate/degrade immediately? Or will they continue to take up space in the landfill? Let students freely discuss those questions.

Draw students' attention to the list on the board or chart. Ask students to copy the list. Then ask them to

  • think on their own about how long each of the items on the list might last when buried in a landfill.
  • recreate the list by writing each item in order according to how long they think it might last in a landfill. Students should start their lists with the item they think will degrade fastest and end with the one that will last the longest.

Next, arrange students into small groups. (Groups of 4 to 5 students will work best.) Let students share their lists and discuss what they believe to be the correct sequence. Ask each group to come to a consensus about the correct order of the items.

Now it is time for the groups to share their lists. Call on one group to share their answers first. Have them tell you the sequence they decided on. As they call out "sheet of paper -- number 1," write a number 1 on the chart next to the words sheet of paper. Do the same for the other groups. When that activity is completed, draw students' attention to the discrepancies on the chart. For example, Why did some people include the sheet of paper before the banana? At the conclusion of the discussion, reveal to students the best guess-timates of scientists, who say the following is the correct sequence:

  • banana
  • paper bag
  • cotton rag
  • wool sock
  • cigarette butt
  • leather boot
  • rubber sole of the boot
  • tin can (soup or vegetable can)
  • aluminum can (soda pop can)
  • plastic 6-pack rings
  • plastic jug
  • Styrofoam cup
  • glass bottle
Point out to students that conditions could result in some items degrading more or less quickly than the list indicates.

Now, turn the assignment back to students. Now that they know the correct order, ask them to brainstorm in their groups how long (how many weeks, months, or years) each item will last. Repeat the procedure above as groups discuss, then share, their best guesses about how long items will last. Then share scientists' approximations listed below:

  • banana -- 3 to 4 weeks
  • paper bag -- 1 month
  • cotton rag -- 5 months
  • wool sock -- 1 year
  • cigarette butt -- 2 to 5 years
  • leather boot -- 40 to 50 years
  • rubber sole (of the boot) -- 50 to 80 years
  • tin can (soup or vegetable can) -- 80 to 100 years
  • aluminum can (soda pop can) -- 200 to 500 years
  • plastic 6-pack rings -- 450 years
  • plastic jug -- 1 million years
  • Styrofoam cup -- unknown? forever?
  • glass bottle -- unknown? forever?
NOTE: The data above was gathered from sources such as the Oregon Department of Environmental Quality.

After you have provided students with data about the longevity of the displayed items, discuss the following questions: What does the data tell you about landfills? Do items continue to degrade and make room for new garbage? Or will those landfills eventually fill up? Do those trash life spans say anything to you about the importance of recycling? Why or why not?

Extension Activities

  • Have students use a graph-making software program to create graphs that illustrate the lifespan of trash items discussed in the activity. If students do not have access to such a program, introduce them to the free and easy-to-use online Create a Graph tool.
  • Have students create posters to encourage recycling the items listed on the chart. Display those posters where students in the school will see them or in prominent public places, such as the library or a grocery store.


Have students write a paragraph explaining what they learned about landfills or recycling from the activity.

Lesson Plan Source

Education World

Submitted By

Gary Hopkins


Don't miss dozens of lesson and project ideas in Education World's Earth Day Archive.
Click to return to this week's Lesson Planning article, Five Lessons Teach Students to Reduce, Reuse, Recycle.

Updated 11/11/2014