What should I do?! Please help me!?

okay, so, there is a group of girls called "the posse" at my school. i've always wanted to hang out with them because there are 5 of them and they are in my cl. most of them i have been friends with before, but now, as a group, they are just plain mean. except for one girl. taylor. she's kinda a follower, but shes my friend. the other day, t and i were just getting annoyed with them. they didn't sit at the usual lunch table. and that was the first day t started hanging out with me, really hanging out with me. so we were really mad and we hard them gossiping about us. so at recess we were just hanging out and hey came over and started telling us that one of them was offended that t's friend made a video of their crazy moments doing their facebook show. and they wouldn't even let us talk and tell them how we feel. so today i got on face-book and , guess what? they all deleted me as my friend. and they did to taylor too. so tomorrow i will confront them and tell my homeroom teacher. but i'm kinda scared. help, please?!