Are there clouds in the sky today? What kind are they? Learn all about clouds and how they fit into Earth's water cycle in this four-book set. From fluffy cumulus clouds to thick stratus clouds and wispy cirrus clouds, find out how different clouds form in the sky. Each title includes audio, comprehension questions, educational front/back matter, full-color photographs, glossary of key words, index, informative sidebars, note to parents and educators, and table of contents. Downloadable Teacher Notes available.