This book for high school students presents 20 different science fair projects that provide an opportunity to learn how plants are affected by natural and man-made influences on their environments. Many experiments in the book were adapted from original International Science and Engineering Fair projects. Each project includes in-depth background information, an overview, a materials list, step-by-step illustrated instructions, procedures for collecting and analyzing data, and suggestions and resources for further study and experimentation (including suggestions for making modifications and creating a unique project). Part I, "Before you Begin," discusses introductory botany concepts, scientific research, and choosing a project. Part II, "Looking for Solutions," Part III, "The Assault on Plants," and Part IV, "Plants and Plant Life," describe the projects. An appendix, "Using Metrics," is a guide to the use of the metric system. The book concludes with a glossary of scientific and botanical terms, a listing of 12 scientific supply companies, 20 sources of information on botany and science fairs, and an index. (LZ)