Keep taking math courses because if you decide to change careers from art to STEM, it will come in handy. Dedicate yourself to a good and solid friendship/study group in college, it most likely won't be the same friends from high school. Also be wise about putting yourself into educational debt-sometimes debt isn't worth it, do the math and understand interest rates. Live in another state a few years, the experiences will give you a whole new perspective. And travel.