Welcome !!
I'm always excited to see young adults getting into reptile ownership. As with any pet it is a big responsibility to care for your snake.
Is there a herpetology club at your school?
I strongly suggest as I do all new comers to make your first corn snake a well started hatchling or a yearling. The good thing is right now most babies will fall into those categories. A well started hatchling would weigh 15+ grams. I prefer 25+ myself. I have decades of experience and I avoid anything under 25 grams unless it is a necessity to my future breeding program.
Make your first experience with a reptile a good one