I currently am a senior (when tuesday comes) at Five Towns. Ill tell you exactly what you need for your audition considering I helped audition some students
Prepare Two pieces from contrasting styles, and bring the sheet music in, whether you can read it or not
Be prepared to sight read a very easy selection of music, and be prepared to sight sing about 4-8 bars of music using solfege.
In terms of song selection, I would chose preparing (arranging) a chord melody of a jazz standard, and one song you are particularly fond of, jazz, fusion, or anything contemporary styled.
In terms of getting accepted into Five Towns, It isn't hard, just the better you do at the audition, the better scholarship you could get.
If you need ANY help at all feel free to PM me.