Convince parents to let me go to homecoming?

I'm a sopre, get good grades, am relatively a good kid and havent done anything really scandalous but my parents didnt let me go to homecoming last year, and now its a different school and i'm afraid that they wont let me again. how can i convince them to let me go this year? its embaring to tell people at school no im not going because my parents wont let me.