Secret Message
Classes 4–10 · about 6 minutes · free, no sign-up
What you will learn
Encrypt and decrypt with a Caesar shift and a keyword, crack a code using letter frequency, and understand why real security depends on a huge secret key.
How to play
- Turn the wheel to choose a shift: the outer letter becomes the inner letter.
- Type a message and lock it, then swap and unlock it.
- Try a keyword code for a harder scramble.
- Finish three challenges, including cracking a spy message with an unknown shift.
Go deeper
Notes, practice questions and tests for the same topic:
Class 6 Maths: Patterns NCERT chapters → Class 8 Computers NCERT chapters →More in Cyber Safety Lab
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Play →Free forever, no account needed. No ads for students and no tracking. Anything you type stays on your device.