Mountains and Valleys: What's the Difference? is aligned to the Common Core State Standards for English/Language Arts, addressing Literacy.RI.3.1 and Literacy.L.3.1a. Full-page color photographs paired with narrative nonfiction text explain differences between mountains and valleys. This book should be paired with "What's the Difference Between Forests and Prairies?" (9781477724491) from the Rosen Common Core Readers Program to provide the alternative point of view on the same topic.