Fred,
Even 20 years ago, I would have said said: The best defense is a strong offense. Nail his ass. First.
Today, things in America are very different than they were when we all went to school.
Nearly all schools now have a policy of punishing all students involved in fighting equally. Never mind who started it, the victim gets punished, too.
All schools are required to report physical violence to the police. The police are no longer permitted to use their god-given intelligence, but must lay every case in front of the district or city attorney...and so on and so on.
In the end, the jerk who started it (I don't give a fcuk about his sexuality, people who attack other people are jerks), ends up being cosseted and pitied (especially if he belongs to a protected group) while the victim gets his whole life ruined, has a permanent criminal justice record and, surprise, surprise, being gay is not a protected class in most places in America.
Fred, I suggest you do the following:
1) Establish a paper trail. Go to the counselor, advisor, principle or home room teacher responsible for you and make sure they take note of this threat. Make very clear that you don't want a fight and are afraid of him. Do not say you will defend yourself if attacked. If the worst happens and you end up decking the bastard, you'll need that record in court.
2)Do your best to avoid him, but if the jerk does attack you, don't pull your punches. Anytime somebody physically attacks someone, they deserve exactly whatever level of self-defense their putative victim chooses. Hit him in the solar-plexus. Hard. Never, ever fight fair. Take a look at some of the advice on defending yourself on YouTube or WikiHow. Some is over the top, some practical. But at least you will get an idea.
3) Start, now, taking a course in self-defense. Many peaceful people confuse the martial arts with violence. Bullshit. There are jerks out there, learning to protect yourself is not violence, it is deterrence.
4) Check the laws on pepper-spray, etc. Almost certainly forbidden to you in your school, but if the cops say you can protect yourself that way without getting expelled, go for it.
5)No idea whether you're gay, nor does it matter. If there is a center for gays and lesbians in your county (bound to be at your university), try talking to someone there. After Matthew Sheppard, a lot of us said, never again.
I have gathered the impression over the last months that you can't exactly talk to your folks about these things? Keep trying.
Of course, as some have pointed out, lots of kids carry serious weapons these days and really do accept permanent physical harm, maiming and death of their victims. We all here are thinking of the harmless bullies and whack-jobs of our childhoods, back in the stone-age. If you are up against a jerk who is armed or who will show up with his friends who will jump you should you have the advantage over him, then this is another situation. I don't think there is anything cowardly about avoiding someone who is willing and ready to slash or shoot you.
Personally, I started school young and had a lot of harassment from kids who were two three or four years older than me. This all came to an end when I hit 6' the summer I turned 11. By 13, I was built like a brick outhouse and even the Mucho-Macho Mexicans knew I was second best shot in our gun club. I may by a lady at heart, but in appearance and bearing, I look like the proverbial not-too-bright over-muscled breeder. That didn't stop the real jerks from attacking me. Finding out I played for keeps did, tho. It sucks, it's stupid, but there just plain are some bullies out there.
One positive note, at my 30th high school reunion, of the seven bastards I went to school with, six had been offed or died. Only one was left. Mother nature, red of tooth and claw, is not over fond of hyper-violent men.
