What would be a good defense for this disorderly conduct charge?

I said What the **** and this teacher heard me at school in the hall.No one else was even close to being around us to hear me she ran off and got a cop. Then i was forcibly taken to their little janitors closet they call a police room from which i denied it constantly.It just sucks because I'm 17 and if i get convicted this goes on my record.