CERCA SLIDES
Ciphers
In this set of CERCA slides, we zero in on the notion of math as a form of communication. By looking at ciphers, students will examine how patterns of letters and numbers can be encoded in the service of privacy, secrecy, security, and brain-teasing fun. Students will not only learn about encryption, they will also create and break codes of their own!
CERCA Slides by Grade

Grade 3: Secret Decoder Wheels
How can people encode and decode a secret message using a shift cipher?(CCSS.RI.3.3-3.10,CCSS.W.3.4)

Grade 4: Encrypting a Shift Cipher
How can people use a cipher key to encode and decode words? (CCSS.RI.4.3-4.9,CCSS.W.4.4)

Grade 5: Shift Ciphers
How can people use a shift cipher to encode and decode secret messages? (CCSS.RI.5.3-5.10, CCSS.W.5.4,5.9)

Grade 6: Affine Ciphers: Secret Messages
Using the guidance in the reading, develop an affine cipher. Using that cipher, create a secret message for someone else to decode. (CCSS.PRACTICE.MP7, CCSS.W.6.1)

Grade 7: Writing and Decoding Affine Ciphers
What affine cipher will you create, based on the information in the reading? What directions would you give to someone trying to decode a message using your cipher? (CCSS.RI.7.1-7.4, CCSS.W.7.9)

Grade 8: Making and Breaking Affine Ciphers
How can you use the information in the reading to code and decode an affine cipher? (CCSS.PRACTICE.MP6, CCSS.W.8.1)

Grade 9-10: Encrypting Secrets
How can you create an affine cipher? (CCSS.PRACTICE.MP7)
