I got a B in art

I made sure to do all my classwork or homework that I have an art, and maybe sometimes I can fool around in art but I don’t say/do anything bad. But every time I tell someone to maybe quiet down a little or tell them to stop cursing so they don’t get in trouble I’m the one that gets in trouble. I really don’t care if a student says anything rude to the teacher or anything else but sometimes when my friends do that I just don’t want them to get in trouble so I tell them to stop so they don’t have to suffer any consequences. But I’m the one who has to suffer the consequences. The teacher is mad annoying and I’m just at the point that I’m not gonna say anything to her and just keep my mouth shut when something happens. Because at the end of the day I don’t care about the teacher and they can fall in a pit for all I care (not to be hash or anything). Also one of my friends that are very loud and like to sometimes ruin the art supplies has a freaking A which makes no damn sense.