We recently had a rainy weekend interrupt our original plans to go geocaching. Instead, I took inspiration from John Baichtel’s recent posting – Codes For Kids – to introduce my kids to ciphers. Specifically the Number-Grid (or Polybius Square) cipher.
The NSA’s CryptoKids website is a great place to help introduce your kids to codes and ciphers. The flash-enabled site sports cartoon-characters and step-by-step instructions on how to encode (and decode) various codes and ciphers. I chose the Number-Grid cipher as one that was appropriate to all my kids.
I started with some loose-leaf paper and a couple of crayons:
From there I wrote out a cipher for each of my kids and showed them how to start decoding the cipher:
My oldest son got the hang of it and wrote a note back to me:
The end result – an hour or so spent at the kitchen table having fun together when we should have been geocaching….if only the weather had cooperated.