The purpose of this assessment probe is to elicit students’ ideas about electric charge. The probe is designed to determine how fast students think electric charges in a wire move. It is best used with high school students. If materials are available, consider demonstrating the probe scenario. A materials list, teacher notes, standards, assessment, safety notes, and references are provided. This book selection also includes the Table of Contents, Preface, Acknowledgments, About the Authors, Introduction, and Index.