The Mouse and the Motorcycle by Beverly Cleary (Kids)

Ralph the mouse craves excitement, but it seldom comes along to his mousehole in the sleepy Mountain View Inn. That all changes when a boy named Keith comes to the inn with his family. Ralph soon sees Keith playing with a toy motorcycle that's the perfect size for a mouse!

When Ralph sneaks out to try the motorcycle, his mother is sure he'll come to no good. Instead, it's just the beginning--for Ralph's motorcycling adventures and, even better, for an unexpected friendship.