Secret Codes

Ennui writing with a pigpen cipher

When you have a lot to say but only want a few people to understand it, you use a secret code!

Codes and Ciphers have been used throughout history to send secret messages right in plain sight…

You’ve already used one cipher during this Mission: the Caesar Cipher that Agent Ennui used to write her message to B.O.R.E.D.

We’re going to play with some other codes and ciphers that have been used by secret agents and spies…

Ennui with the Caesar Cipher

Responsible Adults: 

You can download the Secret Code Instructions if your Motley Agent is working offline! 

pigpen cipher graphic
Image credit  Anomie, Public domain, via Wikimedia Commons


The Pigpen Cipher

The Pigpen cipher has been around for a long time and is easy to take with you anywhere! It’s made by drawing out two tic-tac-toe grids and two X’s and filling in the letters of the alphabet in the grids. The second grid and the second X get dots in them. 

Some people arrange the grids and the X’s differently (so J-K-L-M would be on an X, and then N-O-P-Q-R-S-T-U-V would be on the tic-tac-toe with the dots), so make sure all of your Agents agree on what order the grids go in!   

This is an ancient cipher – nobody knows just how long it’s been in use – and it’s pretty easy to break, like the Caesar Cipher.  Once you know the code, you can decrypt a message without much trouble.  However, it’s still fun to use for passing low-secrecy messages to other Motley Agents. 

Try using the Pigpen Cipher to tell another Motley Agent that the weekly breakfast meeting has been moved to Thursday!


Once you’re feeling good about your skills with the Pigpen Cipher, decode this message before you move on to another ancient cipher: 

a message in pigpen cipher


The word “Scytale” means “cylinder” or “baton” in Greek, so this cipher tells you what you need in its name. 

The Scytale Cipher

Encrypting your message using a different alphabet like the Pig Pen Cipher is one way to send a secret message.  

Another way is to change the way the message looks, and that’s what the Scytale Cipher does.

You will need:

  • Two craft tubes, broom handles, paper towel tubes, or any other good-sized cylinders. It is important that they are the SAME SIZE AROUND
    (you’ll see why)
  • Paper to write on
  • Something to write with
  • Scissors
  • Tape

Let’s send a message!

  1. Use your scissors to cut your paper into long strips about 1/2 to 3/4 inches wide
  2. Tape the strips together so you have one long strip of paper (about 3 strips is good)
  3. Attach one end of the paper to one end of your cylinder with tape 
  4. Wrap the paper around the cylinder in a SPIRAL until you run out of either paper or cylinder, and tape the other end. 
  5. Write your message – one letter at a time – on the spiral of paper. If you want to be SUPER SNEAKY you can leave the spaces out. 
  6. Take your paper off the cylinder and roll it up. 

Decrypting a Scytale Cipher:

Just wrap the paper around your cylinder in a spiral and read the message out. 

It’s super important that you have a cylinder that’s the same size as the sender, or the message won’t make any sense! Try it out and see.


In ancient Greece, legend says that generals would use a soldier’s belt to write scytale messages on so they would be hidden. You can use a piece of ribbon as your paper strip and wrap it around your waist like a belt to keep your messages Top Secret!

a scytale messaage
This is our scytale example!
Ennui examines the scytale cipher
Ennui wishes she had a scytale of the right size

A book cipher needs both of the people to have the exact same book. If you have a different edition, page numbers might be different.




the henchkid does the book cipher

The Book Cipher

The book cipher can be a pretty complicated way of sending secret messages. Motley Agents who are still practicing their reading skills may want to use books that they are familiar with to send simple messages.

Both Agents will need to have the same version of the book. Either you can each have a copy, or you can send the book along with your message. That can be dangerous too, if B.O.R.E.D. intercepts your book!

Sending a message with the Book Cipher:

  1. Choose your book and make sure your Motley Agent Partner has a copy too!
  2. Write down your message. It helps to use common words. 
  3. For each word in your message: 
    1. Find the same word in your book
    2. Write down three numbers with a dash between them:
      • the page of the book
      • the number of lines down from the top to the line with your word
      • the number of words from the beginning of the line to your word

Receiving a message with the Book Cipher: 

  1. Your Book Cipher message should look like this: 12-24-2, 48-17-10
  2. For each set of numbers:
    1. The first number is the page in your book
    2. Starting with line 1, count each line until you get to the second number
    3. Starting with the first word in that line, count words until you get to the third number. 
    4. Write down that word. 

Want to practice your Book Cipher?

Click in this box to download “The Wonderful Wizard of Oz” from OpenLibrary and use it to decrypt this message: 

35-5-2, 38-15-3, 27-4-4, 56-16-2, 135-27-11

  • You’re going to use the page numbers IN THE BOOK to work with, not the ones on the PDF. 
  • The title of the book is at the top of every page. DO NOT count this line. 

Morse Code 

Our last secret code is the most fun! 

Morse Code is a way to send Secret Messages over long distances. It’s still used in many fields today! You can send Morse Code messages using any signal that is able to have a “long” and a “short” message — for example, tones on the radio, notes on the piano,  flashes of light, or puffs of colored smoke. 

An experienced Morse Code operator doesn’t need a cheat sheet (and can send and receive messages at about one word every 2 seconds), but we’ve provided one, because Motley Agents are always learning! 

To send a message in Morse Code, you just look up the message letter by letter on the chart!

  • A “short” tone (dot) is one beat long. 
  • A “long” tone (dash) is three beats long. 
  • You should put one beat between letters.

The most well-known use of Morse Code is the international sign for help: SOS, which you can send as 


Using Light to send messages

You can see light from quite a long way away on a dark night (some scientists have estimated that you can see a single candle from over a mile away if you have a good line of sight), so secret agents and other folks have used lights to send messages for a long time! 

Make two copies of our Morse Code chart and take your Responsible Adult out with you at night. See how far you can send a message with light!

Morse Code is just one way to send a message. In 1775, Paul Revere and his friend agreed on a secret code using lanterns hung in the tower of the North Church in Boston — one lantern if the British troops were arriving by land, and two lanterns if they were arriving by sea. Henry Wadsworth Longfellow’s poem “Paul Revere’s Ride” tells a story of how that secret code helped shape history. 

What secret messages can you send using your new cryptology skills? 


Morse Code Chart

The International Morse Code Chart
Rhey T. Snodgrass & Victor F. Camp, 1922, Public domain, via Wikimedia Commons

The important thing with Morse Code is to keep your timing even.