About two years ago, I absolutely fell in love with mathematics. Since then, I have studied math almost religiously, absorbing everything I can about every subject I can. I have now established what I would call an understanding of most undergraduate topics, up to intermediate complex analysis, some abstract algebra, multivariate calculus, etc.
I really want to get into a good college for mathematics - specifically MIT. As a middle schooler, I have plenty of time before I have to submit an application, and I really want to make the most of that time. You can't exactly put down "was pretty good at math in middle school" on a college application, so I was wondering what things I can do now to get a leg up in the future, that I could put down in a college essay or in my application.
So far I've started a mathematical blog, and I am working really hard to get published by the time I finish high school. My question is - what else can I learn/do/create to give myself a head start in college and in employment as a mathematician?