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An Encrypted Clue

The Math Kids



David Cole

Shannon O'Toole

When Stephanie Lewis finds secret writing in the margin of an old book in the library, the Math Kids have a new puzzle to solve.  But first, they must learn about codes and ciphers, and how to use their math skills to solve them.

As one clue leads to another, the kids are drawn into the mysterious old house that overlooks the town. Is it really haunted like some townspeople say? And who is the man in the long beard who keeps showing up everywhere they go?

But that's not their only problem. Unless they can find a solution, the math competition they've been training so hard for will be cancelled.

Jordan, Stephanie, Justin, and Catherine will need to use all their problem-solving skills to figure out the clues before it’s too late.

The Math Kids: An Encrypted Clue is the fourth adventure in David Cole's popular Math Kids series.

Purple Dragonfly Award – First Place: Mystery

Purple Dragonfly Award – First Place: STEM

Purple Dragonfly Award – Second Place: Middle Grade Fiction

Foreword INDIES Book of the Year Awards Finalist – Juvenile Fiction


September 2024

190 Pages | 6 × 9

Middle Grade (9-12)

ISBN 9781988761985



"Math, logic problems, and puzzles solvable by readers who want to try, all in a diverting chapter-book mystery." – Kirkus Reviews

"As with the other Math Kids books, author David Cole has left readers with a novel that will keep them wondering until the very end." – CM: Canadian Review of Materials

About the Author:

David Cole has been interested in math since he was a very young boy. He pursued degrees in math and computer science and has shared this love of math at many levels, including teaching at the college level, coaching elementary math teams, and running a summer math camp. He also has a love of writing and has written a number of plays that have been performed. The Math Kids was born of a desire to combine his interests and exercise both sides of his brain at the same time. Find him on his website or on Facebook, Twitter, and LinkedIn.

About the Illustrator:

Shannon O'Toole is a Toronto based illustrator, painter and elementary school teacher. Her playful illustration work is inspired by the unique and humorous characters in her life. Aside from illustrating books for children, Shannon has exhibited her artwork in galleries across Ontario. When she is not drawing, Shannon can be found curled up with her dog, Edgar watching old movies. You can visit her online at or follow her on Instagram @shannonotooleart

Related Titles:

The Math Kids The Prime-Time Burglars

The Prime-Time Burglars

The Math Kids An Incorrect Solution

An Incorrect Solution

The Math Kids An Artificial Test

An Artificial Test

The Math Kids A Sequence of Events

Sequence of Events

The Math Kids The Triangle Secret

The Triangle Secret

The Math Kids An Unsolved Proof

An Unsolved Proof

The Math Kids An Unusual Pattern

An Unusual Pattern

The Math Kids A Knotty Problem

A Knotty Problem

The Math Kids The Election Calculation

The Election Calculation

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