MIT OpenCourseWare
All of these materials are great but they are no substitute for in-person instruction and feedback (I don’t mean sitting in a lecture hall watching a professor scribble on the blackboard for an hour).The real value of a professor is that because they know the material they can see the gap in your knowledge, where you’re making the mistake, and quickly get you over the hurdle.This is hard to do when learning by yourself because if you had the knowledge you wouldn’t have gotten stuck in the first place.I wish there were better communities around learning. Discussion bards, forums, etc. have been terrible substitutes in my opinion for in-person learning. Often a big part of my learning comes from helping and discussing the problems with classmates. I’ve learned as much from my peers as I have from professors.