Swinging Girl

Cipher Wheels

It's important for spies to be able to secretly exchange messages! In order to make sure the contents of the message stay a secret, they must encrypt the message! Spies have to be able to exchange messages, but also keep the contents a secret from anyone else! Your spy kid can create their own secret messages with their own cipher wheel.

Try this fun experiment at home and encrypt your own message!

Download this activity!

Watch this video and make your own cipher wheel at home!

Here's what you need

Here's what to do  

Assemble Cipher Wheel

1.  Download, print and cut out the cipher wheel disks.

2.  Align the smaller disk on top of the larger disk. Press the brass fastener through the center (marked with an X) of both disks and fasten loosely in the back.

Encrypt a Code

1. First, select a key that will be used to encrypt and decrypt the message. Pick one letter from the smaller disk, and line it up with a different letter on the larger disk.

      Example Key: Key A:M = Large Disk: A lined up with Small Disk: M

2.  Write out the message you would like to encrypt. Keep your cipher wheel positioned so the letters of your key line up. Find the first letter of your message on the larger disk and write down the letter which appears underneath it on the smaller disk.

      Example Large Disk: SCIENCE

      Example Small Disk: UKEIZKI

3.  Continue, one letter at a time, until your entire message has been encrypted. When you are finished, send your friends the encrypted message (and the key, separately).

      Example Large Disk: SCIENCE IS FUN

      Example Small Disk: UKEIZKI EU HSZ

Questions to ask

Why might you want to send someone an encrypted message?
How will you share the key to decipher your message?
Are there any letters that don’t change when you encrypt your message? Look for patterns.

 cipher wheel 

What's going on?

A cipher wheel is a tool used to encrypt a message. To encrypt a message means to scramble it into a form that is unreadable except to the person with the decryption key. In the case of your cipher wheel, the key is the two letters you must align on the wheel in order to translate the secret message. Encryption is used to protect private data and information that is sent, received and stored online. This type of encryption uses collections of algorithms – sets of computer processes and rules – to create unique encryption and decryption keys.

Use science vocabulary: Use related science words such as cipher, encrypt, decrypt, key and code as you talk and play together. Children learn new vocabulary words when they hear grown-ups use them in context.

Extend your experiments: Create a treasure hunt for your family or friends! Hide a “treasure” somewhere around your home. Encrypt the clues and find ways to share the key with them secretly!

Additional Resources

Ara the Star Engineer by Komal Singh
Hello Ruby: Adventures in Coding by Linda Liukas

Stay At Home Science

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