A celebration and natural history of the helpful ``underground gardeners.'' In warm brown, pale greens, and bright touches of pink and orange, Krupinski uses double-spread cross sections to depict both the soil surface with its plants, animals, and people and the busy earthworms below, effectively focusing attention with her sparse detail, flat shapes, and eye-on-the-ground perspectives. Glaser's brief, child-centered text tells just enough for reading aloud: ``Worms feel sounds with their whole bodies. They feel thunder when I walk.'' The author concludes with more facts in question-and-answer format: ``Do earthworms bite people?''; ``Do worms have a top side and a bottom side?'' A welcome contribution to ecology for the very young. (Nonfiction/Picture book. 3-7)