Ohio Resource Center
Content Supports
Code Crackers
Discipline
Mathematics
9, 10, 11, 12
Professional Commentary

Students begin an exploration of cryptology by first learning about two simple coding methods, the Caesar substitution cipher and the Vigenere polyalphabetic cipher. Students then use matrices and their inverses to create more sophisticated codes. ORC reviewers were pleased at the wealth of coding information provided in this 2-lesson unit but were disappointed that the matrix methods were not fully developed. For this reason, they recommend this site as a content resource, a good reference for background on cryptology. Activity sheets, overheads, discussion questions, lesson extensions, suggestions for assessment, numerous links to supplemental information, and prompts for teacher reflection are included. (author/sw)

Ohio Mathematics Academic Content Standards (2001)
Patterns, Functions and Algebra Standard
Benchmarks (8–10)
C.
Translate information from one representation (words, table, graph or equation) to another representation of a relation or function.
Principles and Standards for School Mathematics
Number and Operations Standard
Understand meanings of operations and how they relate to one another
Expectations (9–12)
develop an understanding of permutations and combinations as counting techniques.
Algebra Standard
Understand patterns, relations, and functions
Expectations (9–12)
generalize patterns using explicitly defined and recursively defined functions;