Distracting people in my course but different classes...

I hate to mention but, I have to say, I've already had enuf of all these kind of people distracting me using vulgar languages. By telling this, I have to recall back by flashing back at one incident that had happened since i've known Tan C.

We were reaching the computer labs early, therefore we went in early to serve the web. Tan C. used to be the 'B' class' friend. She wanted to joke around by hiding one of the 'B' class' guy's thumbdrive in her pocket and later returning as that guy forget to remove his thumbdrive.

Later, that guy came to claim back his thumbdrive but were nowhere to be found. He then questioned a few of us at around his seat area if anyone have seen his thumbdrive. Everyone's remarks were united, which is: No. After a moment, he suspected that it is my friend Tan C. who took it. Though she insisted a no, but from her face I can tell that she's joking. So, the 'B' class' say that she 'steal' that guy's thumbdrive.

After at around 7 minutes, Tan C. returned the thumbdrive to the guy. But instead of the guy scolding us after school, its his 'Girl' friends who came in to confront on us. I helped Tan C. by supporting her whereby the guy's 'girl'friends help him by supporting him. One of that girl's remark was: "If she didn't steal, why would you have to speak up for her?" I was thinking: If that guy want a apology, why must he ask help and support from so many Ah-liens?

From the girl's scolding and negative remarks, Tan C. cried badly. Due to her sadness, she didn't apologise for her joke on the thumbdrive. After she went home, I call her to ask her wherther she's ok.

The very next day, those bunch of 'Bs' started to call us wierd names. Thats why we hate them so much. Can anyone do anything about this matter? I think I should inform the teacher if they cal us this type of name again.