Reading Level 3; Features; Scientific terms are defined in context; Identical dramatic four-color covers (back cover color band identifies books that are the lower level); Teacher"s Guides with reproducible activities allow students to work from either text; Glossary defines difficult terms; "Did you know?" sections contain interesting facts; End-of-book "Facts and Figures" section summarize critical information; The index takes students directly to topics of interest Teach environmental studies and global warming in the inclusive classroom with these unique informational books. Available in two reading levels with identical front covers, so striving readers do not feel "singled out," each title methodically explains the the tough problems faced by our planet plus solutions large and small. Think Green series. Teach environmental studies and global warming in the inclusive classroom with these unique informational books. Available in two reading levels with identical front covers, so striving readers do not feel "singled out," each title methodically explains the tough problems faced by our planet plus solutions large and small.