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 #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 arrive on the one continent they haven’t visited before: Antarctica! What can they hope to learn about happiness in such a barren place? Only the penguins know for sure…Jack and Annie are about to find out!
Formerly numbered as Magic Tree House #40, the title of this book is now Magic Tree...

Merlin the magician will not eat or sleep or speak to anyone. The enchantress Morgan asks young Jack and Annie of Frog Creek, Pennsylvania for help. Jack and Annie know they have to search for one of the four secrets of happiness to help Merlin the magician find joy in his life again. And so they head off in the magic tree house for Florence, Italy, in the early 1500s, then to a misty island in the middle of nowhere, then to the continent of Antarctica....

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...

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 are headed to a land of fierce samurai and great beauty, the capital city of Edo (now the city of Tokyo), in ancient Japan in the 1600s. They bring only a research book to guide them and a magic wand with three special rules.
Formerly numbered as Magic Tree House #37, the title of this book is now

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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 are on a mission to find—and inspire—a musician that brings happiness to millions of people. After traveling to New Orleans, Jack and Annie come head to head with some real ghosts, and discover the world of jazz when they meet a young Louis Armstrong.
Formerly numbered as Magic Tree House...

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 are on a mission to save Merlin from his sorrows! The brother-and-sister team travel back in the magic tree house to the period known as the Renaissance. This time, Jack and Annie will need more than a research book and a magic wand. They'll need help from one of the greatest minds of all time. What

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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 to 18th-century Austria, where they must find and help a musician by the name of Mozart. Decked out in the craziest outfits they’ve ever worn—including a wig for Jack and a giant hoopskirt for Annie!—the two siblings search an entire palace to no avail. Their hunt is further hampered...

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 travel back in time to a desert in the Middle East. There they meet a Bedouin tribe and learn about the way that they live. From camel rides and oases to ancient writings and dangerous sandstorms, here’s another Magic Tree House filled with all the mystery, history, magic, and old-fashioned adventure...