Recently as I was leaving work, walking through the athletic facility, I passed the baseball team waiting for the coach to unlock the door to the indoor training area and the guys who had been in my class in the fall called, "hi, how're you doing?" to me. I greeted them and kept heading toward my car.
Then one of the guys stepped apart from the group and asked if I was going to be coming to watch them play, I should come to some games.
It's nice to get asked.