Mary Pope Osborne

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.

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.

An adventure that will shake you up! That's what Jack and Annie get when the Magic Tree House whisks them back to California in 1906. As soon as they arrive, the famous San Fransisco earthquake hits the city. Can Jack and Annie find the final writing that they need to help Morgan save Camelot? Or will San Francisco be destroyed first?

It's a treasure trove of trouble! Jack and Annie are in for a high-seas adventure when the magic tree house whisks them back to the days of deserted islands, secret maps--and ruthless pirates! Will they discover a buried treasure? Or will they be forced to walk the plank? The magic treehouse whisks Jack and Annie back to the days of deserted islands, secret maps, hidden gold, and nasty pirates.

The magic treehouse 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.

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.

A chilling rescue mission! Merlin the magician and Morgan le Fay have disappeared! To find them, Jack and Annie journey with their friends Teddy and Kathleen to the Land-Behind-the-Clouds, a frozen kingdom of ice and snow. There they find out that the Ice Wizard has stolen Merlin's Staff of Strength, and he won't give it back until Jack and Annie find his missing eye! If Jack and Annie don't return with the Ice Wizard's eye before sunrise, Merlin...

Magically transported to southwest China to find the final object needed to break the spell on the wizard Merlin's beloved penguin, Jack and Annie take a side trip to the world's largest giant panda reserve.

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 carries Jack and Annie to New York City in 1938 on a mission to rescue a magical unicorn from New York City. They arrive during one of the darkest periods in the city's history--the Great Depression. Even worse, the city is in the grip of a terrible snowstorm. Where will Jack and Annie ever find a unicorn in the city? And who are the mysterious people following them? Includes instructions to make a snow globe.