Hnn, Dev. Another idea which has a dual purpose. People are still, at least looking at this thread, getting lost in Hogwarts, and the complaints about this not being a real school sim since everything is static is, honestly, a valid point.
You could fix both those things with some rudimentary AI, I think. Just have each given student select between three states: Standing Around, Chatting, and Going Somewhere. If they're standing around they just find a wall and stand near it, loitering. If they're Chatting they walk up next to another student and loiter near them. And if they're Going Somewhere, they select a certain room and go there.
Then you broadcast which state they're in by making it so that when they change states (which should happen with decent regularity), they pop up a little billboarded dialogue bubble with a randomly chosen string in it, which might have a variable for wherever they're going.
The idea being that if someone's lost, they might notice a student say "I'm going to the Great Hall", and then they can just follow that student as they wander to the Great Hall. This would help people find their way around. And, by giving the students even rudimentary dialogue and having them occasionally move around, you're giving a much better impression that the school is alive and the students have schedules... Even if they really don't.