Ella Schwartz is a government anti-hacking professional and is dedicated to encouraging more young people, especially girls, to explore STEM fields. She lives in Long Beach, New York.

Codes can carry big secrets! Throughout history, lots of good guys and lots of bad guys have used codes to keep their messages under wraps. This fun and flippable nonfiction features stories of hidden treasures, war-time maneuverings, and contemporary hacking as well as explaining the mechanics behind the codes in accessible and kid friendly forms. Sidebars call out activities that invite the reader to try their own hand at cracking and crafting their own secret messages. This is the launch of an exciting new series that invites readers into a STEM topic through compelling historical anecdotes, scientific backup, and DIY projects.

Hands-on history for budding spies, hackers, or anyone with a secret message to send . . . Offer[s] a broad and lucid survey of cryptographic strategies.

This perennially popular topic leads kids into tales of war and espionage, and to better ways of passing messages in class. Cartoon illustrations keep things cheery, as does Schwartz's overall optimism concerning cybersecurity and the white hat hacking. For middle-graders interested in the interplay of encryption and their personal security.