More Secret Codes

We continued working with secret codes this week in Whodunnit? I introduced the classic alpha-numeric substitution code but with a twist. The cipher key showed a table with A=1, B=2 all the way to Z=26, however the code itself showed a number problem in parentheses such as (4+3) which equals 7 and therefore stands for the letter G. For example the word cat would be (2+1)(5-4)(10+10). You could create a variety of math fact problems for each letter of the alphabet using addition, subtraction, multiplication and division depending on your grade level.