Out to everyone at school, but not family. Should I express being gay on assignments or not considering I don't want my family to find out?

I am fairly young and it's a long way to being independent and I am closeted to my family, but open with everyone at school. My problem is that I have to do an assignment that involves a "romantic interest" for play writing and can't decide if I should make it obnoxiously straight in case my family sees or honest (with gay relationship) and hope my family doesn't find out. Unfortunately, my parents attend my HS's meet the teacher night and I just really don't want a teacher to say anything and doing this would let them know I'm gay.No, honesty is not an option. No, I am not independent so it is not up to whatever I think I should do. I need to keep my family in the dark, but should I do my best to not tell my teachers I'm gay in case they talk or tell my family? I think I should probably just fake straightness, but input would be helpful :)