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

The magic tree house takes Jack and Annie to Africa where they meet up with wonderful wild animals, a very hungry warrior, and where they even solve a riddle.

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.

On Christmas Eve, Jack and Annie's tree house transports them to King Arthur's castle at Camelot, where they undertake a quest to the castle of the Otherworld.

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

"With ladders, swings, turrets, and elaborate pulley systems everywhere--animals chase one another over, under, around, and through the tree house that Jack has built. Then the bell rings, and all the animals gather for story time with Jack"--

"A crucial, genre-bending tale, equal parts Ned Vizzini and Patrick Ness, about the life-saving power of friendship. Solomon and Ash both experienced a traumatic event when they were twelve. Ash lost all memory of that event when she fell from Solomon's treehouse. Since then, Solomon has retreated further and further into a world he seems to have created in his own mind. One that insulates him from reality, but crawls with foes and monsters . . ....

While on a mission to prove to Merlin that they can use magic wisely, Jack and Annie travel to seventeenth-century Venice, Italy, to save the city from disaster. Merlin has asked Jack and Annie to help on another Merlin Mission. This time they head back into history to Venice, Italy, in the 1700s. With the help of some new friends, a research book, and a mysterious rhyme from Merlin, the heroes will save the beautiful city from a flood! Yet another...

Who wouldn't want to live in a treehouse? Especially a 13-story treehouse that has a bowling alley, a see-through swimming pool, a tank full of sharks, a library full of comics, a secret underground laboratory, a games room, self-making beds, vines you can swing on, a vegetable vaporiser and a marshmallow machine that follows you around and automatically shoots your favourite flavoured marshmallows into your mouth whenever it discerns you're hungry....

The magic tree house transports Jack and Annie on a mission to the Ice Age where they encounter Cro-Magnons, cave bears, sabertooth tigers, and woolly mammoths.