The 13-Storey Treehouse by Andy Griffiths

Andy and Terry live in the WORLD'S BEST treehouse! It's got a giant catapult, a secret underground laboratory, a tank of man-eating sharks and a marshmallow machine that follows you around and shoots marshmallows into your mouth whenever you're hungry! Just watch out for the sea monkeys, and the monkeys pretending to be sea monkeys, and the giant mutant mermaid sea monster .

. . Oh, and, whatever you do, don't get trapped in a burp-gas-filled bubble .

. . !Well, what are you waiting for? Come on up!Climb more fun-filled levels by collecting all thirteen books in the seven million-copy-selling series – the perfect chapter books for reluctant readers.