Build a Blockchain
Classes 7–12 · about 6 minutes · free, no sign-up
What you will learn
See how each block holds the hash of the one before it, why changing an old block breaks every block after it, and why that makes cheating hard.
How to play
- Look at the four linked blocks. Each one stores the hash of the block before it.
- Be the cheater: change a payment in block 2 and watch the chain.
- Re-mine the broken blocks to fix it, and count the work it takes.
- Then add your own blocks. This is a toy: no real coins or crypto are involved.
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