Explores the details of human and animal bones, comparing the differences between the skeletal structure of various species, with several gatefolds that display the skeletons of many creatures.
Sam, very sad after his dog Ella dies, is persuaded to go out trick-or-treating and is surprised and delighted when Ella--his very own bone dog--comes to save him from a group of rowdy skeletons.
Explains why the skeletal system is important; explains how bones work, describing bones' sizes and shapes, joints, and bones' interaction with muscles; and provides guidance on keeping one's bones healthy.