Mimi's shadow gathers together all the other shadows in the world, and they all run free, around the world, until they find that they miss their homes. By the late author of As I Was Crossing Boston Harbor.
The pictures were fun for kids, but the story progresses as though all shadows in the world are the same at the same time. Maybe the story takes place on a fragment of a ringworld that rotates around its orbit so that it is the same time of day or night on the whole populated surface at any time.