Question about gaining acceptance into a school?

Well, I'll be shocked if anyone actually answers this. Either way, here it goes, I guess. I've loved music, every aspect of music whether it's theory or history since I was younger. I'm going to be in 9th grade in the Fall. There's this school, for liberal arts. My parents said I could apply when the auditions for the fall-spring semester started. My mom is even going to get a letter of recommendation from the treasurer of state. I've been really excited and been checking their website every day. lol All in all, I'm pretty obsessed with this school. I drool over all of the music classes. I have a feeling I would absolutely love it. But,last year I transferred from one school into a charter school. Basically, I slacked off completely. I regret it so much. I wish I could go back and make myself do all the work and do MY BEST. But, I can't. I never officially passed 7th grade. The thing is, I went back to a regular school and they let me into 8th grade. I'm worried that if I audition, that'll come back to haunt me and I won't get into the high school of my dreams. Could anyone..possibly, have any advice whatsoever?