Decoder Ring
What are some ways to encrypt secret messages?
In this lesson, students learn about encrypting and decrypting messages using ciphers. After encrypting messages both graphically and algebraically, students try to decrypt some messages too. In the end, they’ll learn what makes for a useful cipher, and what makes a cipher impossible to decode.
Students will
- Encode messages using different types of ciphers
- Decode messages using different types of ciphers
- Encode and decode messages using graphical representations of ciphers
- Determine what features of a cipher make it a good or bad candidate for encrypting messages
Before you begin
Students should be comfortable evaluating linear and quadratic functions, and should have experience interpreting graphs of functions. This lesson can be used to introduce some concepts from the study of inverse functions; prior exposure to inverse functions isn’t required, though it may help enrich some of the mathematical conversation.Common Core Standards
Content Standards
Mathematical Practices
Downloads
Shoutouts
Ralphie, Little Orphan Annie, Ovaltine
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