Break the Code: Cryptography for Beginners (Dover Children's Activity Books)
By Bud Johnson.
Description
Veteran cryptographer's simply and clearly written how-to book provides youngsters 8 and up with all the information needed to decipher 56 secret messages. Funny cartoons and easy-to-follow instructions explain how to break six different codes, including simple letter grouping, reverse trail, shift code, key word code, date shift code and twisted path code. Examples and solutions. - from Amzon
ISBN(s)
0486291464, 9780486291468
