Little Critter: The Lost Dinosaur Bone by Mercer Mayer (Paperback Book)

Little Critter's class is going to the Critterville Museum of Natural History, and everyone is excited. But when the class arrives, they find out the dinosaur exhibit is closed because of a missing Triceratops bone. Join Little Critter as he searches the Hall of Gems and Minerals, climbs the trees in the rain forest, and sneaks around the Planetarium—all to solve the mystery of the lost dinosaur bone.