Sea Island's Secret
Susan Diamond Riley
Sea Island's Secret
Age Rating, Reading Level & Content Guide
A Delta & Jax Mystery
by Susan Diamond Riley
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
Delta’s fingers dig through damp marsh grass, uncovering a chilling surprise—a hidden skeleton! Suddenly, a secret message from long ago sparks a treasure hunt like no other. But what dangers lurk as Delta and Jax race to save the museum—and uncover a mystery over 150 years old?
Quick Assessment
This middle-grade fiction follows 12-year-old Delta Wells as she uncovers a skeleton and a historic treasure hunt on Hilton Head Island. The story combines adventure with educational insights into Civil War history, making it suitable for ages 9-12. Parents should note the themes of history, mystery, and mild peril, with no graphic content.
Why we rated Sea Island's Secret 9LE
Sea Island's Secret is written at a Level 4-5 reading level across 128 pages. Strong independent readers around grade 5.5 can typically handle this book on their own; with parent or teacher support, Sea Island's Secret works for readers up to grade 6.5.
We rate Sea Island's Secret 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, Sea Island's Secret explores adventure, mystery, historical, family, and science & nature — 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 adventure, mystery, historical.
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
3/10A lighter read — great for independent enjoyment.
Book DNA
Multi-dimensional content fingerprint
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Details
Book Length
- ISBN
- 9781611179767
- Pages
- 128
- Publisher
- Univ of South Carolina Press
- Published
- 2019
- Type
- Fiction