What reading level is The Last Kids on Earth and the Forbidden Fortress?

The Last Kids on Earth and the Forbidden Fortress by Max Brallier is at a Level 5 reading level. Recommended for Middle Grades readers (Ages 9-12).

What age is The Last Kids on Earth and the Forbidden Fortress appropriate for?

The Last Kids on Earth and the Forbidden Fortress is recommended for Ages 9-12. HootRating: 10MP (Moderate — Physical). Content flags: Fantasy Violence, Mild Peril.

What genre is The Last Kids on Earth and the Forbidden Fortress?

The Last Kids on Earth and the Forbidden Fortress is fiction — Juvenile Fiction. Part of the The Last Kids on Earth series.

Does The Last Kids on Earth and the Forbidden Fortress have any content warnings?

The Last Kids on Earth and the Forbidden Fortress has a HootRating of 10MP (Moderate — Physical). Content flags include: Fantasy Violence, Mild Peril. 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 Last Kids on Earth and the Forbidden Fortress?

The Last Kids on Earth and the Forbidden Fortress by Max Brallier is 369 pages.

Reviewed by HootRated editorial · Last updated May 18, 2026

The Last Kids on Earth and the Forbidden Fortress

Max Brallier

The Last Kids on Earth and the Forbidden Fortress

Age Rating, Reading Level & Content Guide

by Max Brallier

The Last Kids on Earth · Book 6

Reading Level 5 10MP Ages 9-12 Matched

The text is written at a 5th grade reading level, the subject matter is intended for middle graders (ages 9–12), and the content has moderate intensity with some emotionally heavy themes.

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About This Book

Jack and his friends are back and ready to face their toughest challenge yet as they infiltrate a mysterious fortress from another dimension. Together, they must stop a wicked villain and the monstrous Thrull from building a dark tower that could threaten their world. Packed with thrilling adventures and clever teamwork, this story keeps the excitement high from start to finish.

Themes

Friendship Adventure Fantasy World-BuildingTeamwork

Quick Assessment

This is a Level 5 book with moderate content intensity. Content themes include fantasy violence, mild peril. Written for readers ages 9-12.

Why we rated The Last Kids on Earth and the Forbidden Fortress 10MP

The Last Kids on Earth and the Forbidden Fortress is written at a Level 5 reading level across 369 pages. Strong independent readers around grade 6.0 can typically handle this book on their own; with parent or teacher support, The Last Kids on Earth and the Forbidden Fortress works for readers up to grade 7.0.

We rate The Last Kids on Earth and the Forbidden Fortress as 10MP ("Moderate — Physical") because the content sits in the "Moderate" range — moderate conflict that may involve loss, scary scenes, or interpersonal stakes. The strongest signals come from physical peril — these are the dimensions parents should evaluate against their reader's tolerance.

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

Thematically, The Last Kids on Earth and the Forbidden Fortress explores friendship, adventure, fantasy world-building, and teamwork — 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.
✓ Readers who like a steady plot with enough momentum to keep pages turning.
✓ Kids drawn to stories about friendship, adventure, fantasy world-building.
✓ Readers who fall hard for one book and want a long series to live in — there are 7 more books in the The Last Kids on Earth series.

Maybe not for

! Readers who get easily upset by emotional or moderately dark scenes — the conflict here is real, not just background flavor.
! Children who are sensitive to violence, even when handled at age-appropriate levels.