Mary Pope Osborne

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.

The #1 bestselling chapter book series of all time celebrates 25 years with new covers and a new, easy-to-use numbering system! Getting the facts behind the fiction has never looked better. Track the facts with Jack and Annie!!
When Jack and Annie got back from their adventure in Magic Tree House Merlin Mission #20: A Perfect Time for Pandas they had lots of questions. What do pandas eat? Where do they live? Why are snow leopards so scarce?...

"When the magic tree house whisks Jack and Annie back in time, they land in the tallest tree in Yosemite, California where they join nature conservationist, John Muir, and US President Teddy Roosevelt on a historic trip through the woods"--

The magic tree house takes Jack and his sister Annie to the Great Plains, where they learn about the life of the Lakota Indians.

Magic tree house series, #21. Jack and Annie are transported by their magic tree house to the time of the Civil War, where they meet Clara Barton.

Magic tree house series, #22. Using their magic tree house, Jack and Annie travel back to the time of the American Revolution and help General George Washington during his famous crossing of the Delaware River.

Magic tree house series, #26. The magic tree house takes Jack and Annie to an African rain forest, where the siblings encounter gorillas and learn to communicate with them.

Using their magic tree house, Jack and Annie travel back to the time of the American Revolution and help General George Washington during his famous crossing of the Delaware River.

Jack and Annie travel in their magic tree house to the land of the mystical selkies to seek a magical sword for Merlin.

The magic tree house takes Jack and Annie to Antarctica to search for the fourth secret of happiness for Merlin.