In this session, students discover some sources of CO2 in the atmosphere and compare their relative concentrations. The primary objective, in addition to being an interesting lab, is to show students that there is a considerable amount of CO2 in car exhaust. This experiment sets the stage for students to understand the role that the burning of fossil fuels plays in warming our planet. A materials list, teacher background information, assessment, safety considerations, standards, references, and resources are provided. This book selection also includes the Table of Contents, Foreword, About the Authors, Acknowledgments, Information for Teaching This Unit, and Index.