Can i change classes in highschool without my parents written permission?

my mom put me in semenary las year and this year too and it pisses me off because i don't get credits for it and i feel that it's a waste of my time. anyway i'm willing to bet that she'll put me in semenary next year (senior year) and i've tried to ask her to elt me take other classes but she demands that i take semenary. what i want to know is if next year i can change classes from semenary to something else next year without a note or anything o0r if i'll have to forge her signature to get out of it. btw i've never changed a class at my school before so all i know about it is that you give the office $5 and they change your class but i don't know what else is required.