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Virtual STEM for Kids: Codes & Ciphers

This guide supports virtual STEM programs for children ages 6-12.

Codes and Ciphers banner

ACTIVITY: Apply your knowledge of ciphers to code/decode messages.

The Science Behind Secret Codes

The Caesar Cipher


Key Vocabulary:

Cipher: a secret way of writing text
Encrypt: convert plain text into a cipher or code
Decrypt: make a coded message understandable
Key: information used to encrypt or decrypt a cipher
Cryptogram: a puzzle with encrypted text
Code: a system of words, letters, images, numbers, or symbols used to replace other words/letters, etc.
Decode: translate/solve a coded message

Create Invisible Ink!

Try different invisible ink formulas and upload a video of your secret message to the STEM for Kids Flipgrid!


Secret messages using water, salt, and crayons:

Heat-activated message using a lemon and heating device (parental supervision required)


Recommended Books

Also available in the following format(s):

STEM Careers: Cryptanalysist