I've found math to be one of the easiest subjects to self learn (though I'm not saying that I've learned it or anything else to any noteworthy degree). The body of inexpensive literature is vast, and education in the field requires less practical support than, say, chemistry, physics, or engineering. I haven't gotten around to laser-induced plasma metal crystal deposition in my garage, but I do have bookcases of read and pending math books in the living room.