Residents on a 63-acre lake in Montcalm County, Michigan, are concerned about the loss of a once-common insect from the ecosystem. In this problem, the challenge to students is to help the homeowners discover what is happening to the Loon Lake ecosystem that would cause a decline in the mayfly population and back their decision with evidence. A materials list, teacher background information, safety practices, references, assessment, and outcomes are provided. This book selection includes the Table of Contents, Preface, Catalog of Problems, Acknowledgments, About the Authors, References, and Index.