The adventures of the four Alden children as they spend a summer vacation on their very own island, purchased by Grandfather's father years ago.

Two brothers take summer jobs at a department store where a series of peculiar events brings them under suspicion.

While on bicycle trip to their aunt's farm, the four Aldens help solve a mystery.

The Alden family rents a houseboat to drift down the river, and encounters a mystery in the little towns along the river, involving a fast black car.

When Rosamond's birthday gift for Nate disappears from her sled, the boy detective decides to unravel the mystery.

Displaying their best work at school in preparation for Parents' Day, Nancy and her sidekick, Bree, are on the case when a prized possession goes missing, in a first chapter book starring the irrepressible Fancy Nancy.

When Cupcake goes missing, Scooby and the gang must search an old house to help find the missing cat.