In this lesson, a brother and sister learn that Venus is visible as either a morning star or an evening star at different times of the year, and they try to explain the pattern of movement of Venus in the sky. Key words and concepts covered are movement of planets relative to Earth. Crosscutting concepts explored are patterns, systems and system models, and stability and change. This book selection includes the Table of Contents, Preface, Catalog of Problems, Acknowledgments, About the Authors, and Index.