Snowbound Mystery: It's an unusual winter vacation for the Alden family when a huge snowstorm traps them in the woods! Luckily, the log cabin where they're staying is cozy -- only there are strange noises in the night and a mysterious code is carved into the closet door. The rescue is a long wait for the Boxcar Children, but the cabin is full of secrets. Tree House Mystery: The Alden children are helping their neighbors build a tree house. From the tree house, the children discover they can see into the attic of the house next door . . . and they notice a window that not even their neighbors know about! Does the old house have a secret? Bicycle Mystery: The Aldens are making the journey to their Aunt Jane's house on an overnight bicycle trip. But on their first night, when the children are caught in a rainstorm and have to take shelter in an old abandoned house, a most unusual mystery -- a lost dog -- finds them!