Mary Pope Osborne

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. Morgan le Fay will make Jack and Annie masters of the tree house if only they can solve four riddles -- which will take four books, of course! Dolphins at Daybreak begins the third set of four books in this magical (and increasingly popular) series! Jack and Annie are off in the Magic...

The #1 bestselling chapter book series of all time celebrates 25 years with new covers and a new, easy-to-use numbering system!
Three …two…one…BLAST OFF! The Magic Tree House whisks Jack and Annie off to the moon—and the future. Their mission? To find the last "M" thing that will free Morgan from the spell. Can they do it before the air in their oxygen tank runs out? Will the mysterious moon man help them? And why is...

Reading level: RL 2.2 ; Ages: 6-9 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 #1 bestselling chapter book series of all time celebrates 25 years with new covers and a new, easy-to-use numbering system!
Jack and Annie head back in time to Venice, Italy in the 1700s. With the help of a research book, a book of magic rhymes, and a set of mysterious instructions from Merlin, the heroes will save the beautiful city from a flood!
Formerly numbered as Magic Tree House #33, the title of this book is now Magic Tree House...

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

When eight-year-old Jack and his seven-year-old sister, Annie, join a group of nineteenth-century explorers aboard the H.M.S. Challenger, they learn about the ocean, solve the mystery of its fabled sea monster, and gain compassion for their fellow creatures.

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

Reading level: RL 2.4 ; Ages: 6-9 When Jack and Annie travel back to the Kansas prairie in search of "something to learn," they gain an understanding of how hard life was for pioneers and they experience the terror of a tornado

The #1 bestselling chapter book series of all time celebrates 25 years with new covers and a new, easy-to-use numbering system!
Merlin sends Jack and Annie on a mysterious mission to Paris, France, over a 100 years ago. There they must find four magicians and give them an urgent message from Merlin himself. When Jack and Annie land in Paris, they make their way to the 1889 World’s Fair. Below the Eiffel Tower, built especially for the

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Jack and Annie are joined by Teddy and Kathleen as they travel to the snowy Land-Behind-the-Clouds, where they search for the eye of the Ice Wizard and attempt to help Merlin and Morgan.