The biggest barrier for me personally in my mathematics education was that it was supposed to be boring, it was supposed to be hard and thirdly you were forced to do an inordinate number of repititions of the same problem untill it nearly killed your brain. Nevermind that spaced repitition would be far more effective.

Before you even debate what to teach you'd better decide how to teach or you're just wasting your time.

Though I suppose my experience may not have been representative, so lesswrong was your mathematics education effective at teaching you what it was trying to teach you?