The Mouse and the Motorcycle by Beverly Cleary

The Mouse and the Motorcycle by Beverly Cleary is a fun middle grade adventure where the reader goes along with Ralph Mouse on his adventures. He lives in a hotel with his relatives between the walls and under the floors. He's told to stay away from humans. But one one he makes friends with a young human named Keith who rescues him when Ralph falls in a garbage can and can't get out without help. Keith lets Ralph borrow his toy motorcycle, just the right size for a mouse. (He can actually make it run by making a motorcycle noise with his mouth.) When he accidentally loses the motorcycle after falling into a load of linens, Keith loses faith in Ralph. But when Keith gets sick and there's no medicine, it's up to Ralph to save the day! Will he be able to find medicine in time to help Keith? Read the book and find out! The Mouse and the Motorcycle

was first published in 1965.