The Alden children are always ready for adventure, and mystery seems to follow them wherever they go. In this exciting collection of four books, the Boxcar Children explore remote mountains, coastal villages, and even a traveling houseboat, uncovering clues and solving puzzles along the way. From surviving a landslide and discovering a hidden secret on a mountaintop, to unraveling strange happenings in a quiet fishing town, to stumbling upon an old clown’s trail in a train caboose, each mystery brings a new setting and a fresh challenge. And during a summer spent on a houseboat, the children can’t shake the feeling that someone is watching them. With each new twist and turn, Henry, Jessie, Violet, and Benny rely on their curiosity, cleverness, and teamwork to get to the bottom of every mystery.

This collection includes:

Book 9: Mountain Top Mystery

Book 10: Schoolhouse Mystery

Book 11: Caboose Mystery

Book 12: Houseboat Mystery