Standing up for myself

I’m 17 & a junior in high school. I’m a super nice person & very quiet. I kind of let people step over me but I’m getting tired of it. I have these friends in a class that kind of belittle me calling me useless & whatnot. They call me the teacher’s pet cause the teacher is always calling me and asks me to help her or to speak out on my answers/opinions. I really never say anything back because anytime I say something, I can feel my face getting super red & it’s embarrassing. Like I said, I never say anything back so I feel weird saying something cause it’s unusual of me. Please help! I don’t want to move cause idk anyone else & I’m socially awkward 😒