From what I've heard, college is much harder than high school. Throughout high school, you can procrastinate and not study very hard and still have a passing grade. In college you need to be very organized and have a tight time schedule, due to studying and classes and homework and time for sleeping also. Sleeping is a very important part to high school and college. Sleeping helps you better focus and helps you retained information better. High school and college exams are very different, college has more information and are given less frequently. I would prepare for exams by planning certain times of when I should study, also keep cards with important information (flash cards) and get lots of sleep.