Middle-grade mystery · adventure · real Oklahoma history

Henry Hail and the Whittier Kids

Middle-grade mysteries filled with adventure, friendship, real Oklahoma history, and the courage to do what's right.

Smart, funny, and clean — the kind of books kids race to finish and parents are glad they're reading.

Read Book One Join the Adventure

Book One available now in paperback & Kindle · Book Two coming soon

Book cover: Henry Hail and the Whittier Kids: Mystery of the Lost Locker

An Adventure Awaits

Perfect for fans of The Mysterious Benedict Society, Encyclopedia Brown, and anyone who's ever believed their school might be hiding secrets.

Mystery of the Lost Locker

Book One · Available Now

Cover: Henry Hail and the Whittier Kids — Mystery of the Lost Locker

Behind the construction fences at Whittier Middle School, Henry Hail and his friends find something that shouldn't be there: a locker dated 1907, sealed and forgotten through a century of the building's hidden history. Inside is a bundle of old letters — and the trail of a vanished student society, a long-ago train robbery, and a cover-up that reaches all the way back to the town's founding families.

Henry would honestly rather stay out of it. But invisible ink, a torn map, and a little sister who notices what everyone else misses keep pulling the Whittier Kids deeper — until the only way forward is to dig up a truth someone buried on purpose. The first Whittier Kids adventure is fast, funny, and built on a simple idea: find the truth, then have the nerve to tell it.

Ages 8–12 · A standalone mystery — a great place to start.

Buy Book One

Henry Hail and the Roosevelt Code

Coming Soon · Book Two

The Roosevelt Code Cover in progress

A school assignment. A forgotten legend. A mystery hidden in Oklahoma history.

It starts with a wrong date. A photo in a school display case says President Theodore Roosevelt visited in 1903 — but Henry's class project says 1905, and Henry can't let it go. Behind that display case is an antique compass that does things a compass shouldn't, once owned by a schoolteacher who saw Roosevelt's real 1905 visit to Oklahoma with her own eyes.

As Henry and the Whittier Kids follow the compass into the archives, they uncover a 120-year-old promise made to their town, a quiet group of "Guardians" who've protected it for generations, and a development company racing to make it all disappear before anyone remembers. To do the right thing, the kids will have to do the hardest thing of all: stand up in public and tell the truth — even when the grown-ups they trust would rather look away.

Meet the Whittier Kids

Four friends, one garage headquarters, and a knack for noticing what everyone else walks right past.

Henry Hail

Henry Hail

The reluctant detective. Dry, analytical, and determined to stay neutral — until the truth makes that impossible. He lives by four words his family taught him: courage, justice, discipline, wisdom.

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

Eleanor

The engine. Decisive, athletic, and three moves ahead, she turns loose ideas into a plan — and a plan into action. (She prefers "decisive" to "bossy.")

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

Nate

The method. Spare batteries, a jeweler's loupe, and one rule: organization is preparation. If it matters, document it.

"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.
Zach

Zach

The wild card. Comic timing, last-minute genius, and a sincerity he doesn't always let people see. Once cracked a century-old lock with a guitar pick.

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

Explore the World of the Whittier Kids

Step inside Henry's Norman, Oklahoma — where the mysteries are made-up but the history is real.

Maps

The neighborhood, the school, and the downtown historic district.

Historical photos

Images from Roosevelt's actual 1905 Oklahoma visit.

Character sketches

The whole Whittier Kids crew, up close.

Behind the scenes

How real history becomes a mystery.

President Roosevelt really did travel through Oklahoma Territory that spring. What the Whittier Kids find there — that part's up to Henry.

The Whittier Kids Series

One garage. One crew. A growing shelf of mysteries.

Book One

Mystery of the Lost Locker

Available now.

Buy Book One →
Book Two

The Roosevelt Code

Coming soon.

Join the waiting list →
Book Three

In the works

More adventures on the way.

Never miss a release →

Why Families Love the Whittier Kids

The Whittier Kids books are written for curious readers roughly ages 8 to 12 — strong enough to satisfy a confident reader, clear enough for a kid just stretching into longer chapter books. The mysteries play fair: every clue is on the page, so readers can solve right alongside Henry.

Underneath the fun, the stories carry something sturdier — friendship, honesty, real local history, and the everyday courage it takes to do the right thing when it isn't the easy thing. They're the kind of books a grandparent and a grandchild can talk about together, and the kind a parent is happy to hand over without a second thought.

Dave Hail III, Author

Dave Hail III

Author & Creative Strategist

Debut novel author and Oklahoma native, David Hail is a writer, creative strategist, husband, and father of two. Inspired by history, mysteries, and kids' imaginations, he blends two decades of nonprofit storytelling into his first middle-grade series. Henry Hail and the Whittier Kids celebrates friendship, courage, and curiosity. When he's not writing, Dave helps organizations tell stories and enjoys family adventures and sports.

Contact Dave