This was one of my calculus teachers in college, around 2006: http://www.jsc.nasa.gov/Bios/htmlbios/akers.html For the skimmers, he was on the Hubble repair mission and held the record for the longest space walk until very recently I believe.
Astronaut aside, he was a very friendly and approachable "good ol' boy", he was an excellent teacher, he was a math major in college himself, he was a principal at a rural school district before joining the military, and in the military did math/physics for missile guidance systems. I don't think you'd find anyone more convincing about the practicality and need of calculating vectors in three dimensions than someone who was plotting missile trajectories for a living. He had great practical examples for the calculus principles being taught.
Understandably every student, myself included, always wanted to know more about his previous career before teaching us calculus since it's not every day you meet an astronaut, and you're a little star-struck (no pun intended) when you've got such direct access to the guy. So to prevent distracting, time consuming and calculus-irrelevant questions during classes he'd set up an Q&A session one night each semester outside class and settle the curiosities. You could kind of tell he didn't really enjoy it, but felt obligated to do it because astronauts are public figures and kind of have to oblige the public a bit, and because it was better than his classes being distracted by it all semester.
The one thing that he said that stuck with me was that since it had been >10 years since he had been with NASA was that his memory of his tasks in space have been blurred from having retold the stories so many times. The actions and the stories have become separate in his mind.
He actually did a ton of other stuff, and was constantly annoyed that everyone ignored it and only ever talked about his moon mission.