"The Mouse and the Motorcycle Series" is a children's book series written by Beverly Cleary. The story follows a young mouse named Ralph S. Mouse who lives in a hotel and dreams of adventure. He befriends a boy named Keith, who introduces him to the exciting world of motorcycles. Together, they embark on various escapades, showcasing themes of friendship and bravery. The series includes several books, starting with "The Mouse and the Motorcycle," published in 1965. It captures the imagination of young readers with its charming characters and engaging plotlines, making it a beloved classic in children's literature.