I got in to CMU for my Masters. Mustered up the guts to quit my job and do it full time. Because I wasn't a citizen (or PR) back then, I didn't get any aid and had no savings at all. I got myself five credit cards and paid my fees with that and then managed to do balance transfers between them and maintained a low interest rate (< 4%) and paid it all within 3 years.

I mentioned this as my "hack" in one of my YC applications and the few who reviewed my app (prior to formal application) all said, "oh this is a known trick. it has been used before". Anyways, I am still happy and proud that took the plunge, did my masters and I am better for it.