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 magic treehouse whisks Jack and Annie back to the days of deserted islands, secret maps, hidden gold, and nasty pirates.

Eight-year-old Jack, his seven-year-old sister, Annie, and Peanut the mouse ride in a tree house to the Amazon rain forests, where they encounter giant ants, flesh-eating piranhas, hungry crocodiles, and wild jaguars.

The magic tree house takes Jack and Annie to a moon base in the future where they continue to search for the fourth thing they need to free their friend Morgan from the magician's spell.

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.

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

The magic treehouse takes Jack and Annie back two thousand years to ancient China where they must find the original copy of an old legend before the Imperial Library is burned down by the evil Dragon King.

No girls allowed at the Olympic games! That's the rule when the Magic Tree House whisks Jack and Annie back to ancient Greece. But when Annie tells Jack to go to the games without her, he knows she's up to something. Will Annie find a way to see the games? Or will she get herself - and Jack - into Olympic-size trouble?

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

The magic tree house whisks Jack and Annie away to Australia where they must save some animals from a wildfire.

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.

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.

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

Jack and Annie travel in their Magic Tree House back to a Hawaiian island of long ago where they make friends, learn how to surf, and encounter a tsunami.

When Jack and Annie travel back in time to Galveston, Texas, on September 8, 1900, they find themselves facing a horrific storm that resulted in the worst natural disaster in US history.

When the magic tree house whisks Jack and Annie back to meet Ben Franklin, they're not sure what their mission is. But Ben Franklin has a mission of his own. Intrigued by Jack and Annie, he's curious to learn more about where they came from. And very curious about their tree house.

When the magic tree house whisks Jack and Annie to a mountainside, they are surprised to find farmers nearby. Then they learn that the farmer's baby llama has been stolen, and Jack and Annie vow to bring the little animal back to its owners. But the journey is treacherous--they must climb to the peak of Machu Picchu and climb back down in order to complete this mission. Jack and Annie have been on many dangerous travels, but can they survive this...

The magic tree house is back with a message from Morgan le Fay telling Jack and Annie to seek out "The Gray Ghost" and listen to her story, and immediately they are whisked away to Nepal where they meet Tenzin, a climber who has recently lost his family, and who takes them up the mountain to meet a snow leopard and renew himself.

"When the magic tree house returns it whisks Jack and Annie away to the Galapagos Islands where they become World Turtle Experts and must save a tortoise in danger of an erupting volcano"--