Dolphins at daybreak: Their magic tree house takes Jack and Annie deep into the sea, where they meet up with dolphins, sharks, and octopi as they search for the answer to an ancient riddle. Ghost town at sundown: Their magic tree house takes Jack and Annie back to the Wild West, where they experience excitement and danger and try to solve a riddle. Lions at lunchtime: The magic tree house takes Jack and Annie to Africa where they meet up with wonderful...

Snowbound mystery : It's an unusual winter vacation for the Alden family when a huge snowstorm traps them in the wood! Tree house mystery: The Alden children are helping their neighbors build a tree house. Bicycle mystery : The Alden's are making the journey to their Aunt Jane's house on an overnight bicycle trip.

Jack and Annie have four time travel adventures involving Alexander the Great, Harry Houdini, Florence Nightingale, and Pele.

When eight-year-old Jack and his seven-year-old sister, Annie, join a group of nineteenth-century explorers aboard the H.M.S. Challenger, they learn about the ocean, solve the mystery of its fabled sea monster, and gain compassion for their fellow creatures.

Eight-year-old Jack and his younger sister Annie find a magic treehouse, which whisks them back to an ancient time zone where they see live dinosaurs.