You can practice the exercises below without using real money — through testnet, visual demos, and explorer research.
🧪 In a visual blockchain demo, change the block data and see how the hash changes.
🔎 Look up a random transaction hash on a public block explorer and read its status, from, to, and fee.
🧾 Fill in a blockchain-vs-database table using a use case of your own.
🔐 Print or save a wallet safety checklist and write out a seed phrase management plan.
🧱 Read a smart contract's function names on an explorer and guess what actions they might perform.
🌉 If you need to use a Layer 2 or bridge, run through a checklist of official docs, fees, withdrawal time, and risk.
You should see
When you practice, don't use real money first. Start with testnet and read-only explorer research.