This book contains 49 science fair projects designed for 6th to 9th grade students. Projects are organized by the topics of soil, ecology (projects in habitat and life cycles), pests and controls (projects in weeds and insects), recycling (projects in resources and conservation), waste products (projects in decomposition), microscopic organisms, and man and the environment. Each project begins with an overview of the subject, suggestions for a possible hypothesis, a materials list, procedures, data gathering and organizational direction, and controls. Contains a resources list, glossary, and index. (MKR)