I think the measure of a great teacher is one who brings a topic alive. I was just reading in the NY Times about a physics professor at MIT who does just that.
. I won't reiterate the content of the article here, I recommend you read it and visit Prof Lewin's online courses to see for yourself the phenomenon…I very nearly became interested in physics. I never have been before.
And, if you doubted for a moment that living in the 21st Century is as good as it gets, MIT have free online courses here. Ignornance can run but it can't hide.