I need some advise...

Being left out sucks, especially if it's a school activity which a big audience has to watch.
Try being lebih social and if anyone ignores while your talking then say "I won't be ignored, anda listen to me pal, I'm the one talking here".
anda should try being lebih demanding is what it is.

Stand up and kick their Ass! If your not going to be accepted naturally, then be accepted forcibly! Be the person that stands up! They start conversations, but anda finish them! If they don't like you, then too dam bad! You're there to perform your role in that play, and they are going to like it! tampil them who anda are!

keep incerting your self until they notice anda thats what i do annoy the shit out of them

I'm not good with advice, so beruang with me.
But, to be honset, if I was you, I would keep to myself a little bit. I'm naturally shy, but this year, especially in my Chemistry class, I didn't know anybody and no one would talk to me.Yet, when they noticed me drawing, the other students came to me asking if I could draw them things, and well, they became social towards me.
So my saran is to tampil them your talent, what makes anda special (in the play especially). It sounds corny but that's okay lol. If they respect and admire who anda are, I'm sure they'll talk to you. If not, they just missed a big chance on getting to know some one truly unique :/ and that's their loss.

^again, I apologize, my saran is not the greatist ^^;