The Mysterious Tadpole concerns a boy who receives a birthday gift from his uncle in Scotland each year. This particular year he receives a tadpole. As the tadpole grows larger and larger, the boy enjoys teaching it to retrieve objects. Eventually, the tadpole grows so large that the boy decides to keep it in the swimming pool of the local junior high school for the summer. When school resumes, the boy must find a new home for his enormous pet. The boy pleads with the librarian to help him raise money to buy the parking lot near his home where a pool can be constructed for the creature. The librarian recalls that a pirate treasure ship was sunk long ago in the local harbor. Since the boy's pet had become so good at retrieving things, it just might be able to uncover the treasure. Sure enough, the creature retrieves the treasure and a pool is constructed for him in the parking lot. The story ends with the boy's uncle arriving at his home with a new birthday present the following year...
