Sleep Schedule

I just dont get why when i am at college it feels nearly impossible to get our of bed before eleven. The entire summer i had work at seven oclock 6 days a week so i though once i came back to school it would be a pieace of cake getting up. I was on a schedule sleeping btw 4 and 6 hours a day and i was fine. Now that i live off campus and have my own place idk what happens but i just cant get up. I have never been a lazy kid thats why i cant figure out what it is about college that turns me into such a bum.