My English teacher used to play bass in a band. They weren't brilliant, but before they disbanded (long after he stopped being my teacher) they got to support Bryan Adams when he came over on tour.
My Italian teacher was something of a libertine throughout his life. He would recount some fantastic stories to us, like outrunning military security in a Fiat, spending some of his teenage life with Buddhist monks, much the rest of it seducing girls (or helping others to do so), complaining against his University's Italian department, traipsing around Italy for a good year as well as out-of-body and premonitive experiences. Every time I talk to him he always has some story that will make my head spin, but I can imagine him doing all of it.
In fact, most of my teachers have had at least some interesting experiences in their lives. Very few, if any, have no stories to tell.