Here's my my advice. With getting into art schools there seems to be two roads
to follow. One: Create a portfolio with your best work in a variety of
categories. Drawing, Painting, Sculpture, etc. OR Two: Create a portfolio that
is comprised of your best work in one category. That being the medium you wish
to continue and master in art school. I honestly would go with number ONE
because you may change your mind about your favorite medium and get a degree in
something totally different. Plus its less of a row-of-the-dice risk then number
TWO.
Like the other guy said always ask your art teacher for help and advise. My
sister is an art teacher for a high school and always sits down with her
students to help them get their heads together about college. I graduated from
Savannah College of Art and Design with a Illustration degree and now work as a
graphic designer. Hope this helps. Good luck! ^_^