Andy and Terry travel through time trying to save their treehouse from highly talented, angry ants and Inspector Bubblewrap the building inspector while rushing to meet their publisher's deadline.

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.

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.

Their magic tree house takes Jack and Annie back to retrieve a lost story in ancient Greece, where they witness the original Olympic games and are surprised to find what girls of the time were not allowed to do.

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.

There's a secret tree fort and you're not invited! In this hilarious and hugely imaginative sibling story from the creator of the internationally celebrated Ike's Incredible Ink, two sisters are told to go and play outside on a beautiful day. The little sister wants them to play together - but the big sister, instead, wants to sit under a tree with a book. So the younger sister decides to tempt her with a description of her super-cool, super-secret...

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.

Eight-year-old Jack and his younger sister Annie find a magic treehouse, which whisks them back to an ancient time zone where they see live dinosaurs.

"Andy and Terry live in a 143-story treehouse. (It used to be a 130-story treehouse, but they built another thirteen stories.) Andy's been a bit stressed out lately, so Terry decides the perfect way to relax would be to head up to their new camping ground level for a much-needed vacation. But it turns out to be not quite as relaxing as planned. Terry forgets to pack the tent and the food, their attempt at fishing ends in disaster, the spooky campfire...

"Andy and Terry live in a 117-story treehouse. (It used to be a 104-story treehouse, but it just keeps growing!) It now has a pajama-party room, a water-ski park filled with flesh-eating piranhas, an Underpants Museum, a giant-fighting-robot arena, and the Door of Doom (don't open it or you'll be COMPLETELY and UTTERLY DOOMED!). For as long as Andy and Terry have been writing books together, Andy has always been the narrator and Terry has always been...