Questions - Chronology, Schoolgrounds

Okay. In 1997, several things happened. I'm confused as to what happened when.

There was a fight between three boys - Bardsley knocked out Martin's teeth and Stuart "bit off" Bardsley's nose. Bardsley and Martin were suspended and Stuart was expelled.

Martin tried to kiss Karen and she rebuffed him. Stuart heard Karen making fun of Martin and laughed at him.

Stuart said she wasn't worth the trouble and was coming between them.

Martin killed Karen, and then Stuart came up and saw what was happening. But if Stuart was expelled, how could he get onto the school grounds? Or was the scrub land not on the school grounds?

I got the impression it was a boarding school; they said Martin's mother killed herself and it sounded like he had nowhere else to go. If it was a boarding school, would the students be allowed to wander off campus?