I've found lately that going to bed relatively "early"- or at least for college students- and waking up a bit earlier makes my day a whole lot better. I feel happier, and I get things done, and the rest of the day just seems to run by so much smoother. I love it.
It's not healthy to stay up late, and wake up, exhaust yourself with school work or other work, and then stay up all night again. It's just not right for our bodies. Some people have trouble sleeping, that is a whole different case which I cannot talk about adequately. But for those who should be able to have normal bodily schedules, should probably start thinking about making their lifestyle's more healthy. Healthier=Happier
It's hard, but it's worth it!