Coinbase has added more tokens that you can earn by watching videos.
The full list of tokens at this point is:
- Zcash
- Basic Attention Token
- DAI
- EOS
- Stellar Lumens
- 0x

It is easy to watch these series of videos and they do a good job of explaining the basics of the different blockchains.
See more here: My Original Article on Coinbase Earn