Skool Daze used a really great idea. You had to be in certain places at certain times, for instance, you had to go for assembly and sit down first thing in the morning. You could go off to explore during break or lunch, or even just write something obscene on one of the blackboards. The thing I enjoyed about it was that the world carried on regardless of what you were doing. If you were late for a lesson because you were up in the loft, then a teacher would search for you and give you lines. If you stood up in the middle of assembly, while everyone else was sitting down, you would get more lines, just like real life
This idea was used again recently in 'Prisoner of War' published by codemasters, where the main character would have to go to roll call and lunch at certain times. Unfortunately Skool Daze was a good game, and 'Prisoner of War' was a very poor game.