I was at Columbia the same time as Obama and don’t remember ever seeing him. Then again, he claims to have lived in off-campus housing and knowing a particular person would depend a lot on whether you frequented the same dining hall on campus or were in similar majors or were both Freshmen at the same time, in which case, you would have to see each other at orientations or run into each other in some of the core curriculum classes (mandatory classes every student has to take). I wasn’t the same year as he was, so for all those reasons, it was not so likely I would have seen or known him at the time.
But an AA student would have stood out, no? You would have remembered him somehow, right? Were there many other AA students attending? Have you seen any pics of him in the annuals?