Books About Coded Messages

The Best Coded Messages Books for Kids

By the Bookroo Editors

Looking for excellent children's books about coded messages? This collection brings together Bookroo's highest-rated and most useful picks in one place.

Start with our editorial favorites, then browse recommendations organized by reading stage to find the right book for your reader.

City of Secrets
#1 in Series
Graphic Nov.
The Valley of Lies
#3 in Series
The 39 Steps
Series
Mask
Series
The Shortlist

Our 9 Favorite Books About Coded Messages

Trust No One
Sale price
$1248
Chapter Book · Ages 8–12 · 2012

Trust No One

By Linda Sue Park · Book #5 in the The 39 Clues: Cahills vs. Vespers series

A hidden traitor threatens Amy and Dan's family. Can they uncover the mole before it's too late?

190 pages· 40,444 words· Est. 5.5 hour read
4.2 Goodreads · 15,375 ratings
$12.99Save 4%
Hardcover
Summary: Thirteen-year-old Dan Cahill and his sister Amy face their greatest challenge yet. With seven family members kidnapped by the elusive Vespers, they must uncover a traitor within their ranks. As time ticks away, Amy and Dan race to identify the mole before another hostage falls. Who can they trust in a world where betrayal lurks in the shadows? The stakes are life and death, and the siblings must act swiftly to save their family and themselves from a devastating blow.
The Blackthorn Key
Sale price
$858
Chapter Book · Ages 10–14 · 2015

The Blackthorn Key

By Kevin Sands · Book #1 in the The Blackthorn Key series

An apprentice races against time to unravel a deadly secret threatening the world.

The E.B. White Read Aloud Honor (2016)Cybils Award (2015)
400 pages· 64,908 words· Est. 7 hour read
4.2 Goodreads · 14,873 ratings
$8.99Save 5%
Paperback
Summary: Christopher Rowe, an apothecary's apprentice, faces a chilling mystery as a cult targets London's apothecaries. With murders closing in on his mentor's shop, Christopher must solve intricate puzzles and codes to uncover a secret that could shatter the world. Can he decipher the clues before it's too late, or will the cult's sinister plan succeed? Dive into a suspenseful adventure where every skill Christopher has learned is put to the ultimate test.
The Case of the Missing Marquess, The Case of the Left-Handed Lady, and The Case of the Bizarre Bouquets (Graphic Novel)
Graphic Nov.
Sale price
$1398
Chapter Book · Ages 9–12 · 2022

The Case of the Missing Marquess, The Case of the Left-Handed Lady, and The Case of the Bizarre Bouquets (Graphic Novel)

By Serena Blasco, Tanya Gold (Translator) · Enola Holmes (Graphic Novel) series

A young detective defies her brothers to solve her mother's mysterious disappearance.

192 pages· 14,312 words· Est. 2 hour read
4.0 Goodreads · 1,951 ratings
$14.99Save 7%
Paperback
Summary: Enola Holmes, the clever younger sister of Sherlock, wakes to find her mother missing, leaving cryptic clues behind. As her brothers plan to send her away, Enola escapes, embarking on a daring quest to solve the mystery. With three intriguing cases to unravel, she must outsmart those who underestimate her. Will Enola uncover the truth and prove her detective skills? Discover the secrets hidden in her notebook and the challenges that await in this thrilling graphic novel adventure.
The Secret Three
Sale price
$333
Chapter Book · Ages 5–8 · 1963

The Secret Three

By Mildred Myrick

A coded message in a bottle sparks a mysterious adventure.

64 pages· 1,569 words· Est. 18 min read
3.9 Goodreads · 117 ratings
$3.50Save 5%
Paperback
Summary: Two boys stumble upon a bottle with a cryptic message, igniting a thrilling quest. As they decode its secrets, they meet a new ally and form a club. What mysteries will they uncover together?
City of Secrets
Graphic Nov.
Sale price
$2184
Picture Book · Ages 8–12 · 2020

City of Secrets

By Victoria Ying · Book #1 in the City of Secrets series

A shy orphan guards a city's secret, pursued by rogues in a mysterious building.

256 pages· 6,162 words· Est. 1 hour read-aloud
3.8 Goodreads · 2,061 ratings
$22.99Save 5%
Hardcover
Summary: Ever Barnes, a shy orphan, guards a secret in a puzzle-like building that powers his city. When Hannah, the owner's daughter, discovers him, their unlikely friendship sparks a thrilling chase. As rogues close in, Ever must protect the secret that could save or doom them all. Can they unravel the mystery before it's too late?
The Valley of Lies
Sale price
$1899
Chapter Book · Ages 8–12 · 2025

The Valley of Lies

By Ali Standish · Book #3 in the The Improbable Tales of Baskerville Hall series

Arthur must betray Sherlock or risk losing everything to save his sister.

304 pages· 66,004 words· Est. 9 hour read
4.1 Goodreads · 113 ratings
$19.99Save 5%
Hardcover
Summary: Arthur faces an impossible choice: betray Sherlock Holmes or lose his sister forever. As he navigates the mysterious Lake District, Arthur becomes a reluctant spy, entangled in a web of secrets surrounding a powerful relic. With his sister's fate hanging in the balance, Arthur must decide how far he's willing to go, risking friendships and his own integrity. Can he outsmart those who watch his every move, or will his deception lead to devastating consequences?
The 39 Steps
Picture Book · 2013

The 39 Steps

By NILL · Usborne Young Reading series

Verify the ISBN before purchasing.

5,472 words
3.8 Goodreads · 17 ratings
Paperback
Summary: Ensure the ISBN matches before buying to avoid errors. This step is crucial for receiving the correct book edition and content.
The Cure
Sale price
$759
Chapter Book · Ages 8–12 · 2023

The Cure

By Terrance Crawford, Dan Widdowson (Illustrator)

Survivors race against time to find a cure and escape the Infected horde.

176 pages· 24,192 words· Est. 3.5 hour read
3.9 Goodreads · 65 ratings
$7.99Save 5%
Paperback
Summary: In a world overrun by the Infected, a small group of survivors must solve a mystery and find a cure before their island is lost. As the horde grows, they face relentless danger and uncertainty. Can they uncover the truth behind the infection, or is it too late to save themselves and their world? The clock is ticking, and every decision could mean life or death in this pulse-pounding survival horror adventure.
Mask
Sale price
$1697
Chapter Book · Ages 8–12 · 2020

Mask

By Kate Hannigan, Patrick Spaziante (Illustrator) · The League of Secret Heroes series

Young heroes face a spy and a sinister plot threatening their city and team.

266 pages· 40,331 words· Est. 5.5 hour read
4.2 Goodreads · 154 ratings
$17.99Save 6%
Hardcover
Summary: Akiko, Mae, and Josie, young superheroes, confront a spy leaking secrets to the enemy. In San Francisco, they join forces with code-crackers to unravel a mystery involving Akiko's mother and the villainous Side-Splitter. As danger looms, can they protect their city and uncover the truth?
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