Developed by:  Catherine R. Ney
Subject:  Life Science
Unit:  Environmental Pollution
Grades:  Middle grades:  4-8
Type:  Structured Experiment

The Impact of Air Pollution on Plants

Objectives:
 1. To test for the presence of one type of air pollution.
 2. To observe the effects of one type of air pollution on plants.
 3. To record the results of one type of air pollution on plants.
 4. To be able to predict the effect of varying amounts of one type of air pollution on plants.

Materials:
 Two, 10-gallon aquariums (leaker aquariums are cheaper)
 Two glass plates (made to fit tightly over each aquarium)
 1-10 pound bag of potting soil
 1 package of marigold seeds
 Two chalkboard erasers (chalked up)

Procedure:
 1. Set up the two aquariums exactly the same.  Cover the bottom of each aquarium with six inches of potting soil.
 2. Plant a dozen marigolds in each, following directions.
 3. Water each aquarium the same amount.  Cover each with glass plate that fits tightly.
 4. Place each in a location where it will receive equal amounts of sunlight.
 5. One aquarium will serve as a control, the other as a test sample.  Students clap two chalkboard erasers together over the uncovered test-sample aquarium.  Then recover it with the glass plate.
 6. Students observe the plants for one week in each aquarium; record their results daily in their logs, (Graph the days of the week, M,T, W, Th, and F on the horizontal axis, the number of wilted plants on the vertical axis, and use two different colored markers to plot each of aquarium's results), and explain results.  What was the effect of adding dust particles to the test-sample aquarium? (Soot in chalk dust is unburned carbon--one form of air pollution.)  What happened to the plants in each aquarium?   Could you vary the amount of chalk dust?  What do you think will happen?
 7. Try to estimate how air pollution affects your community.  Invite an expert in to show you examples of plant, buildings, and other damage done by pollutants.

Evaluation:
 1. Check students' logs on the fifth day to see that their observations were recorded on their bar graphs.
 2. Assess students' success in accurately recording information.
 3. Evaluate students' ability writing predictions and infering damage done by air pollution to communities.