The Hidden
Katherine Applegate
The Hidden
Age Rating, Reading Level & Content Guide
by Katherine Applegate
The text is written at a 4th 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
What if an unstoppable power was just within reach of some very dangerous aliens? Cassie is on the run, trying to stop the Yeerks from stealing a mysterious morphing cube that could change everything. But when the cube starts affecting innocent animals in terrifying ways, the real danger might be closer than she thinks...
Quick Assessment
This middle-grade science fiction novel follows Cassie as she races to prevent alien invaders from gaining a powerful morphing cube. The story includes suspenseful moments and explores the consequences of alien contact, with some scenes involving frightening transformations of animals. Suitable for readers aged 9-12, it includes mild peril and themes of bravery and teamwork.
Why we rated The Hidden 9MP
The Hidden is written at a Level 4-5 reading level across 117 pages. Strong independent readers around grade 5.5 can typically handle this book on their own; with parent or teacher support, The Hidden works for readers up to grade 6.5.
We rate The Hidden as 9MP ("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.
No specific content flags were raised by community reviewers, which is consistent with the moderate intensity score.
Thematically, The Hidden explores science & nature, adventure, friendship, and fantasy world-building — 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.
- ✓ Patient readers who enjoy slower, character-driven stories.
- ✓ Kids drawn to stories about science & nature, adventure, friendship.
Maybe not for
- ! Readers who get easily upset by emotional or moderately dark scenes — the conflict here is real, not just background flavor.
- ! Reluctant readers who need a fast hook — the pacing here rewards patience.
For Parents
Content Intensity
9MP — Moderate — PhysicalReal stakes and emotional weight. May include sustained danger, loss, or bullying.
Was our "Moderate" content intensity rating accurate for this book?
Reading Insights
Hook Factor
2/10A steady, thoughtful read that rewards patient readers.
Discussion Potential
2/10A lighter read — great for independent enjoyment.
Book DNA
Multi-dimensional content fingerprint
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Details
Book Length
- ISBN
- 9780439999151
- Pages
- 117
- Publisher
- Scholastic
- Published
- 2000
- Type
- Fiction