I would suggest you speak to your school counsellor. They are there to help you know. If they can’t help you personally they are in a position to make a referral to someone who can help. This could be anything from a tutor, changing a few classes or dropping a subject or two for the time being. It might be an idea to speak with those at home letting them know that your studies are being affected by this constant arguing. Good luck and God bless you.