That said, todays comic spoke directly to why I teach and articulated it in a way that I have always deeply felt but was never able to say. The opportunity to tell an old story to someone who has never heard it and be there when they have that wide-eyed moment of wonder is the jet fuel that drives science teaching.
On the other hand, the fact that we teach in community not individually means that the jaded and experienced members of your class can be a real buzz kill when it comes to wonder. That of course would be the balancing aggravation to the joy of teaching demonstrative science.