Secret Code Activities for Kids

Fun, age-appropriate code-breaking exercises that introduce children to basic cryptography concepts. Perfect for classroom activities, rainy day fun, or birthday party games.

Kids Activity Sheet

Secret Code Adventures

Difficulty: Beginner (Ages 6-12) | Time: 20 Minutes

Instructions: Become a secret agent! Use the code systems described in each question to encode or decode the secret messages. Write your answers in the spaces provided.

Alphabet Position Reference (A=1 to Z=26)

A=1B=2C=3D=4E=5F=6G=7H=8I=9J=10K=11L=12M=13N=14O=15P=16Q=17R=18S=19T=20U=21V=22W=23X=24Y=25Z=26
Challenge 01 (encode)

Use the Pigpen cipher grid to draw the symbol for the letter A

Hint: A is in the first position of the first grid

Answer: _______________________________________________
Challenge 02 (encode)

Write your first name using A=1, B=2, C=3 code

Hint: Find each letter position in the alphabet

Answer: _______________________________________________
Challenge 03 (decode)

Decode this backwards message: TERCES REPUS

Hint: Try reading the letters from right to left

Answer: _______________________________________________
Challenge 04 (decode)

Decode: 19-16-25 (A=1 code)

Hint: S=19, P=16, Y=25

Answer: _______________________________________________
Challenge 05 (encode)

Write HIDE using the Skip-a-Letter cipher (A=C, B=D, C=E...)

Hint: Move each letter forward by 2 positions

Answer: _______________________________________________
Challenge 06 (decode)

Mirror decode: bOOK (read in a mirror)

Hint: Some letters look the same in a mirror!

Answer: _______________________________________________
Challenge 07 (secret)

Decode the emoji message: sun-1 star-20 star-1 star-18 (numbers = letter positions)

Hint: Convert each number to its alphabet letter

Answer: _______________________________________________
Challenge 08 (encode)

Create a secret code name for yourself using the Reverse Alphabet (A=Z, B=Y, C=X...)

Hint: Z becomes A, Y becomes B, and so on

Answer: _______________________________________________
Challenge 09 (decode)

Crack the code: KHOOR ZRUOG (Caesar shift of 3, shift back)

Hint: Move each letter 3 positions back in the alphabet

Answer: _______________________________________________
Challenge 10 (secret)

Decode: 3-15-4-5 3-18-1-3-11-5-18 (A=1 code)

Hint: Convert each number to its matching letter

Answer: _______________________________________________

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