In this lesson, students explore the process of nuclear fission from historical, scientific, and environmental perspectives. They focus on how nuclear fission is used in pressurized water reactors (PWRs), the type of nuclear reactors most commonly used in the United States today. Students learn about the history of human use of nuclear fission and its societal and ecological ramifications and create a fission model. A materials list, standards, safety notes, teacher background information, assessment, Internet resources, and references are provided. This book selection also includes the Table of Contents, About the Editors and Authors, Acknowledgments, Appendix, and Index.