What reading level is Agent Boo Vol. 1?

Agent Boo Vol. 1 by Alex De Campi is at a Level 3-4 reading level. Recommended for Middle Grades readers (Ages 9-12).

What age is Agent Boo Vol. 1 appropriate for?

Agent Boo Vol. 1 is recommended for Ages 9-12. HootRating: 8LP (Light — Physical). Content flags: Mild Peril, Fantasy Violence.

What genre is Agent Boo Vol. 1?

Agent Boo Vol. 1 is fiction — Juvenile Nonfiction. Part of the TOKYOPOP; Agent Boo series.

Does Agent Boo Vol. 1 have any content warnings?

Agent Boo Vol. 1 has a HootRating of 8LP (Light — Physical). Content flags include: Mild Peril, Fantasy Violence. On HootRated, every book is rated across four dimensions — emotional, physical, social, and thematic — to help parents make informed choices.

How many pages is Agent Boo Vol. 1?

Agent Boo Vol. 1 by Alex De Campi is 100 pages (approximately 5,397 words).

Reviewed by HootRated editorial · Last updated July 16, 2026

Agent Boo Vol. 1

Alex De Campi

Agent Boo Vol. 1

Age Rating, Reading Level & Content Guide

The Littlest Agent

by Alex De Campi

TOKYOPOP; Agent Boo

Reading Level 3-4 8LP Ages 9-12 Matched 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 mild with minimal sensitive material.

Buy on Amazon Listen on Audible Find on Bookshop.org

We may earn a commission from these links. Bookshop.org supports independent bookstores with every purchase.

About This Book

Boo is the tiniest agent in a team that guards countless parallel worlds, but her size doesn't stop her from being brave! When her team rushes off to battle a powerful queen, Boo stays behind with only her clever cat to help defend their home. Together, they face sneaky villains and prove that even the smallest heroes can make a big difference.

Themes

Adventure Friendship Fantasy World-Building Family

Quick Assessment

This is a Level 3-4 book with mild content intensity. Content themes include mild peril, fantasy violence. Written for readers ages 9-12.

Why we rated Agent Boo Vol. 1 8LP

Agent Boo Vol. 1 is written at a Level 3-4 reading level across 100 pages (approximately 5,397 words). Strong independent readers around grade 4.7 can typically handle this book on their own; with parent or teacher support, Agent Boo Vol. 1 works for readers up to grade 5.7.

Read aloud, Agent Boo Vol. 1 takes about 36 minutes, which fits within a single read-aloud session.

We rate Agent Boo Vol. 1 as 8LP ("Light — Physical") because the content sits in the "Mild" range — mild conflict — the kind a child encounters in normal play and sibling life. Across our four dimensions (emotional, physical, social, thematic) the book reads as evenly mild; no single dimension stands out as a concern.

Specific content flags noted by reviewers: Mild Peril, Fantasy Violence.

Thematically, Agent Boo Vol. 1 explores adventure, friendship, fantasy world-building, and family — 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 adventure, friendship, fantasy world-building.