Yes, outside of class. And no, I don't mean that you have to go over to their house and fingerpaint with their kids or anything like that. Although if you get invited, I guess it can't hurt.
False. It CAN hurt. You see, if you go over to your professor's house, then you might be forced to sit there on her couch while her four year old daughter licks your foot. And you won't know how to tell the kid to stop it, because this is your professor and you don't want to be a jerk to her kid. And...