Eight-year-old Jack and his younger sister Annie use the magic treehouse to travel back to the Middle Ages, where they explore a castle and are helped by a mysterious knight.

Jack and his younger sister take a trip in their tree house back to ancient Egypt, where they help a queen's mummy continue her voyage to the Next Life.

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. Morgan le Fay will make Jack and Annie masters of the tree house if only they can solve four riddles -- which will take four books, of course! Dolphins at Daybreak begins the third set of four books in this magical (and increasingly popular) series! Jack and Annie are off in the Magic...

Their magic tree house takes Jack and Annie to the Arctic, where a polar bear leads them onto very thin ice.

Reading level: RL 2.2; Ages: 6-9

The Magic Tree House whisks Jack and Annie off to the moon -- and the future. Their mission? To find the last "M" thing that will free Morgan from the spell. Can they do it before the air in their oxygen tanks runs out? Will the mysterious moon man help them? And why is Peanut the mouse acting so strange!

The magic tree house takes Jack and Annie to San Francisco in 1906, in time for them to experience one of the biggest earthquakes the United States had ever known.

Their magic tree house takes Jack and Annie back to a monastery in medieval Ireland, where they try to retrieve a lost book while being menaced by Viking raiders.

The magic tree house takes Jack and Annie to an African rainforest, where the siblings encounter gorillas and learn to communicate with them.

The Alden children are helping their new neighbors build a tree house when they discover an attic window that not even their neighbors knew about.