Created By: JoAnn Ward, Lance Bryant
Reference: Purdue University, Discovery park
Overview:
This lesson takes approximately 1-2 class periods. It begins with a discussion about cryptography, the science of secrets. We discuss the importance of secrets in today’s world and then focus on a system for sending secret messages used by Julius Caesar around 100 B.C. Students make a Caesar wheel used for encrypting and decrypting coded messages. Students also learn how to crack the code without knowing the encryption key.
Goals/Objectives:
The objectives for this project were to: • Introduce students to an interesting area of mathematics • Challenge students’ conception of mathematics • Provide a connection to mathematics and linguistics • Student analysis of the strengths and weaknesses of the Caesar cipher and using this analysis to both compromise the system and improve it.
Time Required: 50 - 75 minutes
Materials:
• Card Stock
• Scissors
• Paper fasteners
Skills/Knowledge Gained by Learners:
Students make decisions about how to approach problems and communicate their ideas.
Students use strategies, skills, and concepts in finding d communicating solutions to problems.
Students determine when a solution is complete and reasonable and move beyond a particular problem by generalizing to other situations.
Procedure:
This activity is best if done over two days. However this can be shortened. With an accelerated math class this can be done in one period. With other students, if the wheels are made in the last 10-15 minutes of the previous period, the activity can be done in one period. See attachment for more.
Closure: (How to draw the project to a close)
See attachment
Assessment:
Based on worksheets