GOLD MEDAL WINNER IN THE 2015 MOONBEAM BOOK AWARDS. 2015 GELETT BURGESS BOOK AWARD WINNER. Want to learn how to make and break TOP SECRET messages like a real spy? If so, this is the book for you Inside are more than 80 pages of tips, tricks, and practice exercises for writing and deciphering cryptic communications. You'll learn how to make your own invisible ink, hide your messages, create unbreakable ciphers, and craft your own decoder gadgets. Even if you're not interested in becoming a secret agent, you can use this manual to learn how to exchange top secret notes with your friends. Ideal for children ages 8 - 12 years.