What reading level is The 13story Treehouse?

The 13story Treehouse by Andy Griffiths is at a Level 3-4 reading level (Lexile 560L). Recommended for Middle Grades readers (Ages 9-12).

What age is The 13story Treehouse appropriate for?

The 13story Treehouse is recommended for Ages 9-12. HootRating: 8C (Clear).

What genre is The 13story Treehouse?

The 13story Treehouse is fiction — Juvenile Fiction. Part of the Treehouse Books series.

Does The 13story Treehouse have any content warnings?

The 13story Treehouse has a HootRating of 8C (Clear). No specific content flags noted. On HootRated, every book is rated across four dimensions — emotional, physical, social, and thematic — to help parents make informed choices.

How many pages is The 13story Treehouse?

The 13story Treehouse by Andy Griffiths is 256 pages (approximately 9,219 words).

Reviewed by HootRated editorial · Last updated May 18, 2026

The 13story Treehouse

Andy Griffiths

The 13story Treehouse

Age Rating, Reading Level & Content Guide

Monkey Mayhem!

by Andy Griffiths

Treehouse Books

Reading Level 3-4 8C Ages 9-12 Balanced Read Page-Turner

The text is written at a 3rd grade reading level, the subject matter is intended for middle graders (ages 9–12), and the content is gentle with no concerning themes.

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About This Book

Andy and Terry's incredible treehouse stretches thirteen stories high, packed with wild inventions like a see-through pool, a bowling alley, and a marshmallow machine that never stops! Amid flying cats, giant bananas, and sneaky sea monsters, they struggle to finish writing their next book while adventure and chaos keep calling. Dive into their hilarious world where imagination runs wild and every floor brings a new surprise!

Themes

Friendship Humor AdventureCreativity

Quick Assessment

This is a Level 3-4 book with gentle content intensity. No notable content concerns flagged. Written for readers ages 9-12.

Why we rated The 13story Treehouse 8C

The 13story Treehouse is written at a Level 3-4 reading level with a Lexile measure of 560L across 256 pages (approximately 9,219 words). Strong independent readers around grade 4.8 can typically handle this book on their own; with parent or teacher support, The 13story Treehouse works for readers up to grade 5.8.

Read aloud, The 13story Treehouse runs about 1 hours — long enough to span several bedtime sessions.

We rate The 13story Treehouse as 8C ("Clear") because the content sits in the "Gentle" range — no conflict beyond everyday childhood experiences. Across our four dimensions (emotional, physical, social, thematic) the book reads as evenly gentle; no single dimension stands out as a concern.

No specific content flags were raised by community reviewers, which is consistent with the gentle intensity score.

Thematically, The 13story Treehouse explores friendship, humor, adventure, and creativity — these threads give the book room to mean different things to different readers.

Good fit for

✓ Children in the Ages 9-12 range — the maturity and attention span match the story's pacing.
✓ Reluctant readers who need fast-paced, hook-heavy stories to stay engaged.
✓ Kids drawn to stories about friendship, humor, adventure.
✓ Readers who fall hard for one book and want a long series to live in — there are 12 more books in the Treehouse Books series.