Grades 4 - 12: Classroom Waste Audit

Teacher Resources - K-12 Lesson Plans

For a print-friendly version, open attachments at bottom of page.  Print on both sides of paper whenever possible.

Recommended grade level:  4-12
Time required: Minimum of three class periods for waste audit alone, additional time depending on depth and scope of project.

Purpose

This activity will introduce students to the issues of solid waste at your school. After collecting and sorting a representative sample of your school's trash, students brainstorm the most effective way to reduce the solid waste generated in classrooms (and offices). During this lesson, students will exercise critical thinking skills in solving real life problems through use of the scientific method.

Goals

At the end of this lesson students will understand:

• Individual choices can have a large impact overall
• Recycling can be an effective way to reduce the amount of solid waste
• Awareness affects people's actions

Objectives

At the end of this lesson students will be able to:

• Identify the major components of classroom trash
• List items that can be recycled from classroom waste
• Determine and limit the number of variables in an scientific study
• Quantify and analyze results of the initial and follow-up audit

Materials

• Large tabletop or floor space
• Large tarp
• Disposable plastic tarps
• Bathroom scale
• Large trash bags
• Latex or rubber gloves
• Smocks or shirts (to protect clothing)
• Worksheets (these can be duplicated for students or used on a projector)
• Access to soap and water or Disinfectant hand-wipes
• Container in which to measure trash (medium size trash can)
• Trash collected from representative classrooms

Setting up your experiment

• Decide what would be a representative sample of trash from your
  classrooms. What time would be best to collect it? Trash is best
  represented just before custodians collect it. The larger your sample is,
  the more accurate your results are. Also consider including office trash
  to have a variety of school waste.
• Caution should be exercised when handling trash. Do not sort trash from
  bathrooms or kitchen. Be on the lookout for anything that could cause
  injury. If any of your trash presents a problem roll it up in a disposable
  tarp and discard it. Replace the disposable tarp with a new one.
  Classroom Waste Audit
• Determine how you will record the results of your sort both by weight
  and by volume. Have students determine the volume of a medium sized
  trash can. Use this container to measure your trash by volume.

Procedure

• Explain the steps you will take.
• Collect the trash. Keep track of which classrooms were sampled and
  how they were combined.
• First, spread tarp on table or on the floor. Then place a disposable tarp
  on top of the first tarp. One student will dump the trash on to the tarp,
  while other students separate the sample into categories and others
  measure, weigh and record data. (You may have to group classroom
  trash together to obtain a measurable amount. For example, combine
  all of the 4th grade classrooms, all classrooms sampled on the second
  floor, etc.) If your sample is large, you may want to divide the amount
  between several groups of students. Students who handle trash should
  wear gloves and smocks.

As you sort trash the categories you will use include:

recyclable paper

aluminum

steel

glass

plastic

food waste

other waste (used paper from the kitchen or bathroom, facial
tissues, anything that does not fit into other categories)

• Using the scale and the measured trash can container, students weigh
  and measure sorted trash. Depending on the size of your sample
  multiple sets of scales and containers will save time. One container and
  scale for each group of students is ideal. Have students record the
  results both by weight and by volume. They may have to estimate the
  volume of some materials.
• Combine your group totals on a worksheet or overhead.

For discussion questions, results, and extensions, open the print-ready lesson plan below.

Attachments:

File	Description	File size	Downloads	Last modified
Quantification Worksheet - Volume/Cubic Feet	Downloadable worksheet suitable for printing	3 Kb	109	06/08/10 07:53
Quantification Worksheet - Pounds	Downloadable worksheet suitable for printing	3 Kb	92	06/08/10 07:53
Waste Audit Results Worksheet - Volume/Cubic Feet	Downloadable worksheet suitable for printing	2 Kb	103	06/08/10 07:53
Waste Audit Results Worksheet - Pounds	Downloadable worksheet suitable for printing	2 Kb	90	06/08/10 07:53
Classroom Waste Audit - Lesson	Downloadable lesson plan suitable for printing	32 Kb	238	06/08/10 07:52