Why do so many students grades drop so much once they enter college?

<p>I went to a high school with a 39% graduation rate, that just got off the country’s needs improvement list. So I did no work and graduated near the top of my class.
I don’t go to a notoriously hard school by any means, but a lot of classes have little to no curving, and there is definitely no grade inflation. But most of my peers at that school come from top high schools, and therefore knew how to study. I never studied for a test in my life before getting to college. Hence, my grades went down.</p>