Objective: 

Students will explore methods of secret communication used during the Revolutionary War, such as ciphers and hidden messages, and create their own substitution cipher to compose a secure message.

Materials Needed: 

• Paper

• Pencils

• Cipher wheels or substitution cipher templates

• Historical context reading materials

Steps:

• Introduction: 

  • Students discuss the importance of secret communication during the Revolutionary War. 

  • Provide historical context on how ciphers and secret codes, such as those used by George Washington's spies, helped secure information.

• Group Activity: 

  • Students will be introduced to the concept of substitution ciphers, where each letter in a message is replaced with another. 

  • In pairs, they will create their own substitution ciphers and use them to encode a message related to the Revolutionary War.

• Testing and Refining: 

  • Once they have created their ciphers, students will exchange coded messages with another group, attempting to decode the secret information. 

  • Afterward, they reflect on how well their method protected the message.

Equity and Access: 

Provide cipher templates with clear instructions for students who need extra support, and pair students with diverse abilities to ensure collaborative problem-solving.

Real-World Application: 

Connect the lesson to modern-day cryptography, explaining how similar encryption methods are still used to secure digital information, such as online banking.

CS Practice(s): 

• Developing and Using Abstractions: Students abstract the letters of the alphabet into coded symbols, learning how simple encryption can secure messages.

Standard(s): 

• CA HSS.8.1

• CA CS 6-8.NI.6

Objective: 

Students will learn how to use steganography, the technique of hiding information within digital images, to secure a message. They will explore how this method protects digital information from unintended readers.

Materials Needed: 

Computers with steganography software or access to online tools, images for embedding messages, reading materials on cryptography and steganography.

Steps:

• Introduction: 

  • Students explore the concept of steganography and how messages can be hidden inside digital images, similar to how secret letters were concealed during the Revolutionary War. 

  • They consider the benefits and challenges of steganography in modern-day cybersecurity.

• Group Activity: 

  • In pairs, students will use steganography software or an online tool to embed a hidden message inside an image. 

  • The message could relate to historical themes from the Revolutionary War, such as instructions for the Continental Army.

• Testing and Refining: 

  • Students will swap images with another group and attempt to decode the hidden message using the same software. 

  • They will evaluate how well their method concealed the information and how easily it could be detected.

Equity and Access: 

Provide written instructions and step-by-step tutorials for using the steganography tools, ensuring students with varying technical skills can participate. Pair students with different strengths to encourage collaboration.

Real-World Application: 

Discuss how steganography is used today in cybersecurity to protect sensitive data, such as hiding information in digital files or images.

CS Practice(s): 

• Creating Computational Artifacts: Students use digital tools to create a computational artifact (an image with a hidden message), applying cryptographic techniques to secure information.

Standard(s): 

• CA HSS.8.1

• CA CS 6-8.NI.6