ciphers

While preparing for a fund-raiser antique show, Trixie and the other members of the Bob-Whites discover a secret code in the pages of an old magazine in the attic.

Learn to create secret codes using symbols, dots, lines, rearranged letters and more.

Presents several easy codes with messages to decode and directions for making and writing with invisible ink and devising one's own code.

Examines a number of different ways of writing secret messages, including invisible ink and a variety of ciphers. Gives suggestions and aids for code-breaking.

Presents a variety of codes and ciphers and includes messages to encode and decode, nearly all of which are part of a story.

At the reading of their grandmother's will, Dan and Amy Cahill are given the choice of receiving a million dollars or uncovering the 39 clues hidden around the world that will lead to the source of the family's power, but by taking on the clues, they end up in a dangerous race against their own family members.

Trying to solve coded messages leads the Critter Kids to a new member for their club.

Three friends form a codebreaking service and meet a motley cast of characters including a Bulgarian spy, a man from the State Department, and a little old lady who wants her diary encoded.

A history of codes and cryptography, discussing ciphers from Julius Caesar to quantum cryptography and profiling cryptology and decryption experts. Includes code breaking exercises.

Tells the stories of ninety-five situations in which code and hidden messages have been used throughout history.