Math-wise, well, it's a matter of where I go to college, I figure it'll have a huge effect on basically everything that happens thereafter. I definitely want to continue on my path towards understanding the Weil conjectures and that kind of thing, so I plan to be able to compute sheaf cohomology for schemes by the end of the year and learn more algebraic number theory. (And maybe look at representation theory.)

CS-wise: learn enough ClojureScript to be able to make convincing mathematical (etc.) visualizations -- I recently got a taste of Figwheel+Reagent and I'm hooked! -- and be able to manipulate Haskell transformer stacks better.

Other than that, I'd like to learn some French (marathoning Engrenages was the best decision ever!) and not forget the little German I know.