How to Invent Your Own Secret Code with Your Kids

Learn simple ways to create fun secret codes and ciphers that kids of all ages can make and crack together.

1. Start with a Simple Letter Substitution Code. The easiest code to create replaces each letter with another letter or symbol. Try the classic Caesar cipher: shift every letter three places forward in the alphabet, so A becomes D, B becomes E, and so on. When you reach the end, wrap around (X becomes A, Y becomes B, Z becomes C). Write out the regular alphabet on top and your coded alphabet below it as a reference key. Practice by encoding simple words like your family's names or favorite foods.
2. Create Symbol-Based Codes. Design your own symbols to represent each letter of the alphabet. Use simple shapes like circles, triangles, squares, or lines in different positions. You could also use numbers, where A=1, B=2, C=3, and so on. For a fun twist, create symbols based on things your family loves – if you're into sports, use different ball shapes or stick figure poses. Draw your symbol key on paper and keep it handy while you practice writing messages.
3. Try Number Pattern Codes. Use your phone's keypad to create codes where each letter corresponds to the numbers you'd press to text it. For example, A=21 (press 2 once), B=22 (press 2 twice), C=23 (press 2 three times). Another option is to use book codes: pick a favorite family book and use page numbers, line numbers, and word positions to spell out messages. The first word on page 5, line 3 might represent the letter that word starts with.
4. Make Picture and Color Codes. Create codes using drawings or colors instead of letters. Assign each letter a simple doodle like a flower for A, a sun for B, or a house for C. You can also use color patterns – red might mean A, blue means B, green means C. For younger kids, try using stickers in different patterns or shapes. Take photos of different objects around your house and assign each one a letter value.
5. Test and Improve Your Code. Once you've created your code, test it by writing simple messages back and forth. Start with short words and phrases like 'hello' or 'pizza tonight.' Time how long it takes to write and decode messages – if it's too slow or confusing, simplify your system. Make sure everyone in the family understands how to use the key. Consider creating multiple versions: an easy one for younger kids and a more complex one for older family members.
6. Put Your Code to Use. Use your secret code for fun family activities. Write coded treasure hunt clues, leave mysterious lunch box notes, or send secret messages between family members. Create a family code book where you write down all your different codes and keep adding new ones. You might develop special codes just for certain occasions, like birthday surprises or vacation planning. The more you use your codes, the faster and more creative you'll become.