This series makes learning about sustainability a fun endeavor and features a familiar cast of characters. Elmo and Abby explain where their trash goes, Big Bird finds simple ways to fight pollution, and Oscar the Grouch convinces readers to reduce, reuse, and recycle. Easy-to-follow explanations (the importance of only flushing certain things down the toilet; the benefit of conserving water while doing common activities like -brushing teeth) are provided alongside full-page illustrations and color photographs of actual cleanup efforts. The visual representations of ethnic, racial, and ability diversity are a notable component, and the simple text makes this series accessible to readers as young as age four. VERDICT A great series that is ideal for any early learning collection.--School Library Journal, Series Made Simple-- "Journal"