Can i sue my school??

I got to a really conservative school and they force us to gender EVERYTHING. They're like fascists. I've tried to change the outlook but to no avail. We have a goldfish in one of the classrooms whose gender they've just flat out assumed and forced on them. I was caught in the classroom after hours giving a PowerPoint to the fish that they can choose their gender and to not listen to the oppressive regime I'm forced to call a school. I've come to the conclusion they go by the pronouns they/them and have started using them around others to hopefully encourage them to do the same. They took me to the headmaster's office and told me they were going to expel me for