Mary Pope Osborne

The magic tree house transports Jack and Annie to the deck of the Titanic to find a mysterious gift that will free a small dog from a magic spell.

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

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

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.

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.

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.

The magic tree house takes Jack and Annie back in time to feudal Japan where the siblings learn about the ways of the Ninja.

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...

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

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.