Middle-grade mystery, Oklahoma kid detective book, best books for ages 8-12, adventure books for boys and girls, Henry Hail series

🔍 Henry Hail and the Whittier Kids 🔍

A Middle-Grade Mystery Adventure

Get ready for mystery, laughter, and unforgettable friendships!

Henry Hail and the Whittier Kids book cover showing four kids investigating a mystery

When Henry Hail and his friends stumble upon a long-lost locker during renovations at Whittier Middle School, they uncover cryptic letters, a rusted key, and clues pointing to a 1907 train robbery—and a secret society determined to hide the truth. As the Whittier Kids follow the trail across school grounds and hidden tunnels, they must outsmart rivals before the mystery disappears forever.

📚 Available Soon

🔍 Meet the Whittier Kids

Henry Hail character illustration
Henry Hail

The observant leader with an exceptional memory and talent for spotting patterns and details others miss. When mystery calls, Henry reluctantly steps up to guide his friends.

"We need to be systematic about this," Henry insisted, consulting a color-coded checklist he'd created.

Eleanor character illustration
Eleanor

The confident strategist and adventurer who's quick to take action when others might hesitate. Her bold thinking keeps the team moving forward.

She shrugged. "Tell that to my eyes, Henry. They don't lie."

Nate character illustration
Nate

The tech-savvy researcher with a knack for uncovering hidden connections. His gadgets and analytical skills help solve the toughest puzzles.

"If it's a locker, the dimensions are off by about two inches for the standard models used at the turn of the century," said Nate. By now, the group was never surprised when Nate had a random or arcane fact in his head that applied to almost every situation.

Zach character illustration
Zach

The creative thinker whose humor lightens tense moments while his quick thinking and improvisational skills get the team out of tight spots.

"If there is a portal in there, dibs on using it to skip Miss Johnson's class."

📖 Why You'll Love This Book

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Mystery & Adventure

A fast-paced middle-grade mystery packed with humor and teamwork that will keep readers guessing until the very end.

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Puzzles & Codes

Full of secret codes, old maps, and thrilling discoveries that will engage curious minds and problem solvers.

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Real Oklahoma History

Incorporates authentic local history and landmarks, making learning come alive through adventure and mystery-solving.

Zach unzipped the main compartment, and an avalanche of snack packages spilled onto the floor—beef jerky, trail mix, candy bars, three different kinds of chips, and what appeared to be an entire box of granola bars. "We might get hungry," he said defensively. "Are we exploring a cave or setting up a convenience store?" Eleanor asked.

—Chapter 18, "Gear Up for Adventure"

History isn't about choosing sides—it's about understanding the whole story.

—A moment of reflection on legacy and truth

Perfect for fans of The Parker Inheritance, Framed!, and The Mysterious Benedict Society—where every clue unlocks a bigger truth.

- For ages 8–12 (and adventurous grown-ups too!)

If you loved City Spies, The Westing Game, or The Book Scavenger, you'll race through this fast-paced, history-fueled mystery.

- Perfect for mystery lovers!

First in an exciting new series! Book two, Henry Hail and the Whittier Kids: Secret of the Station Master, coming Summer 2025.

- More adventures await!

📚 Reader Resources

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For Educators

Classroom discussion guides and Oklahoma history connections available for teachers and librarians.

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For Families

Perfect for family read-alouds and sparking conversations about teamwork and problem-solving.

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Book Clubs

Engaging discussion questions and activities to enhance your reading group experience.

📖 Get a Taste of the Adventure

"Open Sesame," Zach said, and the locker creaked open. Inside, they found not dust—but a time capsule of secrets: letters, trinkets, and a map whose edges had frayed with age.

—The moment everything changes

Henry's bedroom looked like a tactical command center had exploded. Maps, printouts, and strange diagrams covered his desk, while an open duffle bag on the floor was steadily accumulating supplies for tomorrow's expedition to Robbers Cave.

—Setting the scene for adventure

✍️ About the Author

Dave Hail is a writer, creative strategist, and lifelong lover of great stories. A husband, father of two, and Oklahoma native, he draws inspiration from history, mysteries, and the boundless imagination of kids. With two decades of experience crafting compelling narratives for nonprofit organizations, Dave brings his storytelling expertise to the world of middle-grade fiction. Henry Hail and the Whittier Kids is his debut novel and the first in an adventurous series celebrating friendship, courage, and curiosity.

📬 Contact David

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