I'm doing the lightning one right now with chaincode. It's great. They've managed to create a good online curriculum while maintaining accountability by hosting a series of weekly discussions (one 1-on-1, one 4 person, and one group discussion per week). They also do a good job of selecting people who are committed.
Do you recommend the lightning one over the bitcoin core one? I am new to both, have some basic understanding of SHA256/elliptic curve cryptography/C/JavaScript/Python. Little confused on which one to select [though been holding since 2014]