You step up to a ledge and look down into a canyon that is two miles deep. Where on earth are you? Extreme! Earth introduces some of the most radical locations on planet Earth.Spectrum® Readers are the perfect Common Core aligned tool to support the development of nonfiction reading skills crucial to a young reader’s success. Each leveled reader features high-interest informational content exciting full-color photo illustrations and Common Core aligned comprehension practice focused on the development of critical thinking skills. This multilevel series is the perfect addition to any library at school or home.