Cairo v1:

https://github.com/starknet-edu/starknet-cairo-101

https://github.com/shramee/starklings-cairo1

Cairo v0:

Hello, Cairo — Cairo documentation

https://github.com/onlydustxyz/starklings

(will most likely be updated to Cairo 1 soon)

https://github.com/starknet-edu/starknet-erc721

https://github.com/starknet-edu/starknet-erc20

https://github.com/starknet-edu/starknet-messaging-bridge

https://github.com/starknet-edu/starknet-debug

https://github.com/starknet-edu/starknet-accounts

Run your own Starknet full node: