Why am I being bullied at school?

I'm bullied at school and nobody takes it seriously?

Hello, I am (f) 15 years old and am in 8th grade. I've been bullied a lot since grade 5. The fact is that I was and am apparently bullied because, from a purely visual point of view, I "don't fit into my class." It started in the 5th that the classmates blasphemed about the fact that I was very tall and very slim (I was about 165 cm tall at the time and the others in the class were all 155 cm at most). So I didn't really fit in optically. I tried to make friends with people for a long time anyway and then stood with the others (I have to say, we are only 7 girls in the class). At some point, however, it annoyed me that everyone looked at each other in disgust when I came and I also noticed that they were blaspheming about me and my appearance, so I looked for a girl who was nice but also not exactly popular. For the past few years I was always alone with her in the school playground during breaks! The boys in the class also bully me: They say I'm shabby and look like a zombie, sometimes they kick and push me too. I was also bullied because I was relatively good at school. In terms of clothing, I also tried to dress like the other trendy girls, but then also led to people gossiping about it. Unfortunately, the school isn't exactly big either, so the whole thing has even got around in other grades: Lately I overheard someone from the 10th grade (whom I don't even know) said quietly to her friend, me she would be sorry !!! At the moment we have a theater project at the school and I am supposed to perform there with a "popular girl" from my class. She then said the following to my teacher: "I won't perform with her, she is too long for me (I am 173cm tall), too skinny and too pale!" (The teacher didn't say anything, the other students laughed and agreed) I told my parents about it very early on (in 5th / 6th grade), but unfortunately they didn't take me seriously and the whole thing played down. I would just imagine it and it couldn't be that nobody likes me and everyone blasphemes about me. If so, then maybe something would be wrong with me (with my character?). So at some point I stopped talking to them about it, because their reaction only made things worse for me. What should I do, I can't take it anymore !!!