The Mouse and the Motorcycle — Beverly Cleary

Ralph the mouse was terrified. All he had wanted to do was ride the little motorcycle someone had left on the table. Instead, both Ralph and the motorcycle had taken a terrible fall -- right into the bottom of the wastepaper basket. He was trapped, left to wait for whatever fate was in store for him.

But it turned out to be Ralph's lucky day. Along came Keith, the owner of the toy motorcycle, who was staying with his family in the hotel room where Ralph lived. Not only did Keith save Ralph's life, but he taught him how to ride the bike. And, when everyone was asleep, he turned Ralph loose in the hotel halls to enjoy the biking adventure of his life. But adventures can be both fun and trouble...as Ralph and Keith soon found out!