What if you could challenge your 11th graders to figure out the best response to a partial meltdown at a nuclear reactor in fictional Gammatown, USA? With this volume in the "STEM Road Map Curriculum Series," you can! "Radioactivity" outlines a journey that will steer your students toward authentic problem solving while grounding them in integrated STEM disciplines. As are the other volumes in the series, this book is designed to meet the growing need to infuse real-world learning into K-12 classrooms. This interdisciplinary module uses project- and problem-based learning to help students understand the debate over the safety and efficiency of nuclear power for meeting the country's energy demands. Teams of students will apply what they learn about the science and history of nuclear energy to convey the views of particular stakeholder groups and propose solutions to the crisis. At the end of the module, students will be able to do the following: (1) Explain how radioactive decay, nuclear fission, and nuclear fusion work; (2) Model nuclear fission, create computer-generated simulations, and perform mathematical computations; (3) Calculate the energy yield of an individual nuclear event (decay, fission, and fusion) and use exponential functions to represent chain reactions; (4) Identify the safety and environmental concerns involved in using nuclear fission in power plants; (5) Explain the history of nuclear energy use and identify key milestones that have influenced society's perspectives on it; and (6) Make a presentation about solving the crisis from their stakeholder group's perspective. The "STEM Road Map Curriculum Series" is anchored in the "Next Generation Science Standards," the Common Core State Standards, and the Framework for 21st Century Learning. In-depth and flexible, "Radioactivity" can be used as a whole unit or in part to meet the needs of districts, schools, and teachers who are charting a course toward an integrated STEM approach.