The secret of the invisible city
Dale Bick Carlson
The secret of the invisible city
Age Rating, Reading Level & Content Guide
by Dale Bick Carlson
The text is written at a 4th grade reading level, the subject matter is intended for middle graders (ages 9–12), and the content is mild with minimal sensitive material.
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About This Book
Jenny steps through a shimmering portal and finds herself in Krishna-la, a city made of sparkling crystals where aliens grant the wildest dreams. Just as her friends start to explore, a mysterious shadow flickers across the sky—what could it mean?
Quick Assessment
This middle-grade science fiction mystery follows Jenny and her friends as they explore Krishna-la, a dazzling alien city where fantasies come to life. Suitable for ages 9-12, the story encourages imagination and problem-solving, with mild suspense and no intense content.
Why we rated The secret of the invisible city 9LE
The secret of the invisible city is written at a Level 4-5 reading level across 135 pages. Strong independent readers around grade 5.5 can typically handle this book on their own; with parent or teacher support, The secret of the invisible city works for readers up to grade 6.5.
We rate The secret of the invisible city as 9LE ("Light — Emotional") 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.
No specific content flags were raised by community reviewers, which is consistent with the mild intensity score.
Thematically, The secret of the invisible city explores mystery, science & nature, adventure, and friendship — 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.
- ✓ Kids drawn to stories about mystery, science & nature, adventure.
Maybe not for
- ! Readers looking for something heavier — this is a gentle, low-stakes story by design.
For Parents
Content Intensity
9LE — Light — EmotionalLight conflict or tension. Mild peril resolved quickly.
Was our "Mild" content intensity rating accurate for this book?
Reading Insights
Hook Factor
3/10A steady, thoughtful read that rewards patient readers.
Discussion Potential
1/10A lighter read — great for independent enjoyment.
Book DNA
Multi-dimensional content fingerprint
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Details
Book Length
- ISBN
- 0448190044
- Pages
- 135
- Publisher
- Grosset & Dunlap
- Published
- 1984
- Type
- Fiction