my old class before i switched schools was like that. apparently when they all went to high school everyone hated them because they still hadnt grown out of that but they were doing high school tier things like going out and drinking underage and getting the entire grade in trouble even though it was just the dumb people from my old school in that grade, and not the entire grade at the high school. it only takes a couple of bad eggs to ruin things for everyone. my sister was a grade ahead of me and she had friends in my grade on the track team who couldn't stand people who came from that school and was surprised my sister did. because it was my grade. thats why i had to switch schools
theres this thing, and you'd think people would grow out of it but its not always the case, where people just like to see how much they CAN get away with. like they know better but they just wanna see, and that sort of like, gives them some sort of pleasure, if they can push the line as much as they can
but even among my old school's grade, i can say with confidence, the problem even among them was probably only three or four individuals, who the others were lowkey afraid of and just sort of mimicked to be "cool" and no one had the guts to go against it. so honestly, if you know who the real problem people are, you can probably at least figure out who to sort of connect with.
social survival sort of falls on making friends who are mostly just like classroom-only friends, so even if they're not like sharing interests with you, just like having someone to laugh with between classes or at lunch, about stuff happening at school, helps a lil bit. and you may end up with a few close friends that you'd see outside of class that are actually really cool long time friends, but most people i met in school i never kept in touch with.