Gilbert Strang's linear algebra course blew my mind back in high school, and I still use insights from it every day. Strang has a particular lecturing style where he approaches every topic several times, often beginning many lectures before the main treatment. At first I thought it was a bit confusing, but later I realized it helped build fluency, just like a language class.
I'm really thankful to MIT OCW for putting his lectures out for free -- in fact, I think I'll go donate to them now.
I'm really thankful to MIT OCW for putting his lectures out for free -- in fact, I think I'll go donate to them now.