In junior high, we had a frequent substitute teacher whose last name was Cumm. We couldn't believe it when we found out his first name was Richard.
Also, in high school, there was a math teacher whose name was Alec Dick. On our schedules, under our classes it would say the teacher's first initial and then his last name, so a lot of us had math class with A Dick. Of course, being the type of kids we were, we had to circulate the joke about his wife's name being Ivanna (it was a total buzzkill when we learned what her name actually was).
I'm cross posting this in various places for some self congratulation as well as some thanks to various online friends who have offered kind and supportive words over the years, please feel free to ignore: