The CryptoClub materials teach cryptography as an application of mathematics topics from the middle-grade curriculum.

The CryptoClub Cipher Handbook is the centerpiece of the CryptoClub curriculum. It is a student reference and workbook that is recommended for use in informal learning environments such as afterschool and enrichment programs. It introduces ciphers in a way that encourages problem solving and reasoning and provides engaging messages to encrypt, decrypt and crack. The Cipher Handbook can be used with whole-class instruction or with self-paced work in small groups. See the Table of Contents (pdf). 88 pages. $12. Authors: Janet Beissinger and Bonnie Saunders. Available only through the Bookstore of the University of Illinois at Chicago.
The CryptoClub Leader Manual accompanies the CryptoClub Cipher Handbook and helps teachers lead a CryptoClub program. It provides suggestions for teaching, along with an answer key, and discusses connections to middle-grade mathematics. It also describes games and activities that provide students with additional practice in an engaging, informal way. 142 pages. $31. Available only through the Bookstore of the University of Illinois at Chicago.

The Cryptoclub: Using Mathematics to Make and Break Secret Codes follows the story of the Cryptokids as they teach themselves about cryptography and mathematics. This book is well-suited for use by independent learners and homeschoolers. In addition to the six ciphers covered in the CryptoClub Cipher Handbook, it includes a chapter on the widely-used RSA cipher. It has additional chapters on modular arithmetic, factorization, and exponents, and describes historical connections to cryptography. 200 pages. $43. Available at the Bookstore of the University of Illinois at Chicago, and other places where books are sold.
CryptoClub.org is a website where students can learn and apply cryptography. It includes many tools for encrypting and decrypting, messages to crack, games to enjoy, comics to read, and more. There are also tools for teachers to create activities for their students.
CryptoClub Connections to CCSSM (pdf) details connections to the Common Core State Standards for Mathematics(CCSSM).