This single-concept unit on garbage is a "do-it-yourself" approach to environmental education. The emphasis is on composting or microbial decomposition under controlled conditions since composting appears to be one practical way of handling garbage. More than 30 simple experiments show some of the changes that garbage undergoes. The garbage pollution problem is made meaningful by considering what kinds of garbage and how much garbage each student and his family produce, and how it is handled in the community where they live. Most of the activities require only simple, readily available materials--for example, garbage, soil, aspirin, nails, and steel wool. Diagrams and fill-in charts supplement the informative and procedural explanations. The approach to study is interdisciplinary since it involves mathematics and social studies as well as science. The unit may be used in grades K-12 and it is suggested several activities be conducted simultaneously to be most effective. A related document is "Teaching Science with Soil," SE 015 688. (BL)