Ask HN: Is there an open source curriculum for for a mathematics degree?

The hard part about learning math is not finding course material. Three or four textbooks can cover the entirety of undergraduate mathematics. The real challenge is in the discipline, focus, practice, and repetition of doing problems over and over and over again. It can be almost impossible to force yourself through this, and it's really easy to start glossing over things you think you understand. The only real way to learn math (short of possessing genius level autodidacism) is in a classroom setting, with a teacher and peers, receiving constant feedback and assessment. I would strongly suggest you check out the local university or community college if you have a serious desire to learn.