This was more entertaining than previously thought. My thwarted attempt to register online was still in the system, so they knew which classes I wanted; that was good, since I had left my course manual in my dormitory and hence couldn't look them up. But the lady doing the registration apparently noticed something unusual, so summoned her supervisor, who was as perplexed as she was.
"You're in the Engineering school?"
"Yes, I've been here for a year."
"Hmm." *sounds of typing* "Who are you here with?"
"What do you mean? My advisor is Professor Kenneth J. Goldman..."
"Uhm... okay. Right, you're going to be starting next fall?"
"It will be my third semester- uh, here's my student ID."
"But the system says you're underage- but you're already in- it- is this wrong?"
At that point, my father stepped in to the conversation. "No, he's 17, and he's been here for two semesters and the Freshman Summer Academic Program..."
"Oh. Uh, let me clear that hold for you..."
Ah, it's fun being a 17-year-old freshman at a college set up for 18- and 19- year-old freshmen. No, sincerely- I found the entire exchange highly entertaining. I like watching people get confused over my youth!
Not that the topic usually comes up until official records of me are retrieved. Guesses I've recieved for my age so far vary from 18 to 23, but never on this campus have I actually had a correct first guess without the person to whom I am speaking already being explicitly made aware that I'm younger than most. My CS 241 professor (Dr. Sally Goldman) guessed that I was a sophomore (no, I'll be a sophomore when I'm in her 400-level class next semester), people I've worked with on Physics problem-sets in frantic last-minute forbidden collaboration in the TA office tend to guess me as the same, one of the workers at Bear's Den, Anita, was honestly surprised to discover that I'm not yet a junior...
(Insert unrelated rant here about living in a state where the age-of-consent is 17 and you can't buy condoms until you're 18. Not that it's relevant to me.)