The purpose of this assessment probe is to elicit students’ ideas about different types of circuits. It is designed to find out the reasons students use to rank the brightness of bulbs in three different types of circuits. This ranking task probe is best used with middle or high school students. In both cases, these probes can be used either as preactivity or as a formative assessment during a unit on electric circuits. Be sure to explain how to use the symbols to rank the brightness of the bulbs. 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.