Crack the Code! 15 Books About Puzzles and Codes for 9- to 12-Year-Olds

by Dena McMurdie

Photography by Seana Williamson

My 11-year-old daughter loves puzzles, ciphers, secret messages, and mysteries. She even took an online class through Duke University to learn more about codes and ciphers throughout history. The best part was that our entire family got sucked into the class. We spent every afternoon pouring over coded messages and using various ciphers to crack them. It was a blast.

Of course, my daughter also wants to read every book written on the subject — fiction and nonfiction alike. She devours them with an enthusiasm usually reserved for eating chocolate cake.

Filled with secret codes and tantalizing mysteries, these 15 books will keep your child glued to the page.

Editor’s Note: This article was originally published in 2019 and updated in 2022.