Encryption Basics | Really Private Messaging

Made by Mozilla with thanks to April King's "Intro to Cryptography"

45 minutes

Participants will learn the basic importance and mechanics of encryption, modeling public-private key encryption schemes with simple tools like paper and markers, crayons, or colored pencils, thereby learning how to collaborate, connect, evaluate encryption schemes, and secure their communications online..

Participate on the Web

21st Century Skills

Collaboration Communication Creativity Problem-solving

Web Literacy Skills

Collaborate Connect Evaluate Protect

Learning Objectives

  • Understand encryption as a way to keep private information secret from eavesdroppers.
  • Understand how public-private key encryption works (a.k.a. asymmetric or RSA encryption).
  • Create simplified public and private keys to model asymmetric encryption.
  • Understand encryption best practices for beginner users.


  • 13+
  • Beginner users of encryption.


  • Internet-connected instructor computer
  • Markers, colored pencils, crayons, paints, or any other coloring tools that easily mix.
  • Paper
  • Optional: internet-connected computers for participants