Texas Instruments: Numb3 Rs: Straddling Checkerboard

Based off of the hit television show NUMB3RS, this lesson introduces students to a ciphering technique called the Straddling Checkerboard. In such an encryption scheme, all messages are turned into a series of numbers for transmission. While the cipher is a bit confusing, this lesson does a good job of describing it, and students will be able to catch on to the straddling checkerboard with the examples present in the lesson.