Treehouse series

Who wouldn't want to live in a treehouse? Especially a 13-story treehouse that has a bowling alley, a see-through swimming pool, a tank full of sharks, a library full of comics, a secret underground laboratory, a games room, self-making beds, vines you can swing on, a vegetable vaporiser and a marshmallow machine that follows you around and automatically shoots your favourite flavoured marshmallows into your mouth whenever it discerns you're hungry....

"Andy and Terry are once again inviting readers to come hang out with them in their astonishing 39-story treehouse (it used to be 13 stories, then 26 stories, but they keep expanding). And this year they will have even more time to jump on the world's highest trampoline, toast marshmallows in an active volcano, swim in the chocolate waterfall, pet baby dinosaurs, and go head-to-trunk with the Trunkinator, since Terry has created the greatest invention...

Before they can go up, they have to go back—travel through time with Andy and Terry as they attempt to save the treehouse!

New York Times bestselling author Andy Griffiths invites readers to come hang out with him and his friend Terry in their 65-Story Treehouse-the fifth book in the illustrated chapter book series filled with Andy and Terry's signature slapstick humor!
Andy and Terry live in a 65-Story Treehouse.

...

When their over-the-top ideas expand their amazing treehouse to include a giant submarine sandwich shop and a human pinball machine, Andy and Terry find themselves babysitting Mr. Big Nose's three troublesome grandkids.

"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...

"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...