In this lesson, students use the law of conservation of momentum and energy to investigate the forces and motions involved in three scenarios—a car striking a stationary object, two vehicles colliding head-on, and two vehicles colliding at an angle to each other. After students analyze the conditions, they practice reverse engineering the scenarios to gain skills needed for the final challenge of the module. We recommend reading Chapter 3, which is included in this book selection and provides a module overview and summary. A materials list, safety notes, standards, assessment, teacher background information, Internet resources, and references are provided. This book selection also includes the Table of Contents, About the Editors and Authors, Acknowledgments, Appendix, and Index.