How do I prove im not gay?

you have no obligation to prove anything to anyone.They're just messing with you.Don't pay attention.
Why would you be so upset over this?

Get a girlfriend?

I always find it quite disturbing when 13 year olds try to pressure each other into having sex. Just tell them it's not true that you are gay.

Describe your interaction with the boys for us.

I'd like to know whether your friends are taunting you for a good reason, or if they are just taunting you because they know it bothers you.

Whatever the case, don't try to prove anything to them. Guys love to tease one another. If you are sensitive and get your feelings hurt by this, then it is like bleeding in shark infested waters. Once they smell blood, they go into a feeding frenzy.

Trying to prove that you're straight to them would be like thrashing around while you're bleeding in shark infested waters. Don't do it.

My advice is for you to learn how to be okay with who you are. If you know you aren't gay then it shouldn't matter what your friends say. Their false claims don't make you any less right about yourself. Having this kind of confidence will allow you to laugh this off and to even have fun with it. Being a guy requires that you have thick skin. You have to be able to give as well as you get. Sometimes you're going to be the butt of a joke, and other times you'll be the one who is making the joke.

well, just pull down your underwear and show them. lol

but make sure it's straight enough!!!

Just kidding!!!

But why care?!

guys being in guy groups and girls being in girl groups is only normal
don't let it go to your head

what I'd personally do is go to the one saying I'm gay, lightly palm his cheek and say
eeew, you goose little boy, (and a bit more silently) your ass is mine today

but that's my friends and my jokes

to prove it, get a gf
or at least try dating a girl even though you know nothing will happen much
just show her off to your friends or at the least introduce them

By becoming religious, religion is the solution for everything! Even wars, oh wait,

You might ask them to stand naked in front of you and see if you get aroused.
However, they must all do this at the same time, so they can all see which of THEM is aroused.

Still, they are just messing with you.

As Ted Haggard's case indicates, those who rant and rave most loudly against homosexuality, are trying to convince themselves that THEY are not really homosexual.

A real friend would never ask you to "prove" anything about yourself. I suggest you get some new friends.

well every time someone calls you gay you just call them a big boy or something and squeeze their bum and wink

they probably know your not gay so just by doing stuff like that will embarrass them and they'll shut up. If anyone actually thinks you might be, they're going to think it more if you look like your trying to desperately prove you're not or they can see you're getting upset about it!