Each double-page spread of this square-sized picture book introduces one of twelve species of dinosaurs with a statement that begins with, “I wonder …” The answer is found when one lifts the flap hidden somewhere on the page, in the setting or on the dinosaur itself. The text provides simple facts and theories about dinosaurs—what they ate, how they moved, how big they were—while the structure of the narrative models and inspires scientific inquiry on the part of young children. The search-and-reveal aspect of the illustrations will also encourage their active participation. Boldly colored collage illustrations are stylized and yet realistic enough to satisfy budding paleontologists. The endpapers show the relative size of all twelve dinosaurs in silhouette, accompanied by a pronunciation guide in the front and added facts in the back. (Ages 2–6)