The creators of One Bear (1998) and Pumpkin Day, Pumpkin Night (1999) turn in another polished take on a perennial classroom science topic. After their teacher brings in a potted milkweed and a mail-order kit, a group of children watch three caterpillars eat, grow, form chrysalises, and emerge as monarch butterflies. Halsey’s pictures, all neat lines and cheery faces, are constructed by layering cutout paper figures, for a low-relief effect that adds visual interest without compromising each scene’s simplicity. After the butterflies are released, the children write to a class in Mexico, and get a letter, with a photo of a butterfly-covered twig, in return. Rockwell expands on the teacher’s matter-of-fact explanations of what’s going on at each stage with a helpful note, and Halsey depicts ten other named, common butterflies, both in mature and caterpillar form, on the endpapers. Though not detailed enough to be an instruction manual, this is good to go for general background reading, nutritious fodder for newly hatched lepidopterists, or as a storytime prelude to Sam Swope’s infectious Gotta Go! Gotta Go! (2000). (Picture book nonfiction. 5-7)
