Population:
This activity can be adapted to any population. If it is for beginning-level ESOL you will want to introduce suitable vocabulary and concepts around trash and recycling before doing this activity.

Objectives:
Students will investigate some of the factors that influence the decomposition of trash and discuss how accumulations of trash can have long-lasting and far-reaching effects on our society.

Materials:

• Clean dry (non-food-related) bags of trash
• Collection bags
• Disposable gloves
• Journals
• Beakers
• Stopwatches
• Stirring sticks
• Several different brands of toilet paper
• Liquid hand soap for hand-washing or liquid waterless soap substitute

Activity 1:
Trash Trek
This is best done in an outdoor venue like a park, school/program yard, etc. Search the school yard or a local park or seashore for trash types. (If collecting trash is not an option, ask the custodian of your program to save a bag of dry, non-food related trash for you) Supply each student with plastic gloves, bag or bucket for holding trash, science journal and pencil.

Review/Some Rules:
Dry trash only. (If in doubt, ask the teacher.)
Manmade objects only (no twigs, nuts, stones, etc.).
Back in the classroom, have students spread out trash and sort it by type and amount.

Questions:
(You may need to review some of the highlighted vocabulary and concepts before asking/discussing the questions.)

• What are the most common objects found in the trash?
• Which items could be reused as is?
• Which items could be cleaned and reused?
• Which items could be broken down and reshaped into useful items?
• Which items are not reclaimable?
• Which items will degrade within a year?
• Which items will be around in 10 years?
• Which items will be around in 100 years? 1000 years?
• Are there alternatives to the longest lived items?
• What are the pros and cons of the alternatives? (Cost? Function? Availability?)

Follow-up:
Students could be asked to speculate about long-term problems associated with certain kinds of trash. Students could be presented with specific activities (drying hands with a paper towel, using a disposable paper lunch bag, wrapping birthday presents) and asked to brainstorm as many creative alternative materials or alternative processes as possible that would reduce the amount of trash generated.

Activity 2:
Rate of Decomposition
What sorts of things affect the rate of decomposition of trash? Have students bury different items and dig them up at different intervals to see which decomposes fastest. You might supply some of the items for them, such as an apple slice, piece of toilet paper, and Styrofoam cup, and then ask them to bring in three other items on their own. The items can be buried outside in a garden type plot if it will be left undisturbed by others all year. The items can also be buried in plastic milk jugs with the tops cut off and kept indoors, allowing access even in winter months. If using milk jugs, allow students some choices about the conditions in the jug, such as:

• How does the type of soil affect the rate of decomposition? (Use identical objects in two containers, but use sand in one, potting soil in the other.)
• How does the amount of moisture affect the rate of decomposition? (Use identical objects in two containers, but spritz one with water periodically.)
• How does the temperature affect the rate of decomposition? (Use identical objects in two containers, but put one in the refrgigerator, and one on a heater.)
• Does it matter whether the container is sealed or open? (Prepare identical containers. (spread plastic wrap or foil over one.)
• How does the appearance of objects change over time?
• Does the weight of the objects change over time? If so, how can you explain this?

Variation:
Toilet Paper Activity
Students can compare how quickly different brands of toilet paper break down in water. Students should have several beakers containing identical amounts of water all at the same temperature. A stopwatch is useful to measure the speed at which fibers begin to separate, signaling that the paper is breaking apart. Students can stir the paper gently, but should be careful to stir each one with equal force and speed.

• Can you come to any conclusions about the properties of different brands?
• Does the rate of dissolving correlate to any other characteristics of the paper (softness, strength, thickness, etc.)?
• Do the fastest dissolvers have any characteristics in common?
• Is there a relationship between speed of dissolving and price?
• Does the temperature of the water make a difference?
• Does it matter whether you crumple the paper or drop it in flat?