First week in most schools is orientation. They take the whole class and stick them in a big hall and have you guys mingle for about 6-7 hours a day. Its mandatory to come. You are just meeting each other.
But the very first day of class.... is nothing different than regular college. One big difference I noticed between undergrad and dental school was that you don't move around too much. The professors are the ones who come in and out. The students just sit in the same room until day is over or you have sim lab.