The purpose of this assessment probe is to elicit students’ ideas about the ocean and seas. The probe is designed to reveal whether students use geographic names and locations to consider the number of separate oceans and seas or use the concept of “one ocean.” This probe is best used with grades 6–12, and should reinforce the idea that we have only one ocean that is connected to all oceans worldwide. A materials list, teacher background information, references, assessment, and outcomes are provided. This book selection includes the Table of Contents, Foreword, Preface, Acknowledgments, About the Authors, Introduction, and Index.