How bad does this affect my college chances?

Tisch is 50% about your audition/portfolio and 50% about your academics. So, although you don't have to have as good grades as CAS students have, you still need good grades. They do take into account the school you go to and of course how you do on your SAT etc. I do know of dancers who have gotten into the dance program with probation because of their grades. However dance is more reliant on the audition then other Tisch Arts, due to the level of expertise required to get into the program. My daughter got accepted to Tisch with grades better than yours, but no AP courses. That is because she spent time at her ballet academy after school. She took 6 hours of dance a day. She was a grad of LaGuardia Arts. H.S. (the FAME school) as a dance major there.