Please don’t trust any one part or detail of my description. It’s been a really long time. May have been a made for TV movie. Guessing somewhere between late 80’s and late 90’s.
I think the movie started with someone being strung up in the woods. The setting is a school. There is a group of students sort of policing it called the sentinels(?). It’s like a club led by an instructor. They wear the same (bomber?) jackets. The lead is a female wanting to take these fascist / racist bullies down. There is a “punk” who stands up to them. Maybe a fight in the cafeteria. He is later chased by them and disappears, seemingly dead, but comes back at the end saying he hitched a ride to a ska festival.
That’s all I remember.