Why did I get better grades for courses when I didn't study, than when I spent nights without sleeping so I could study?

Sometimes to much studying isn’t good

If studying kept you up all night, then it sounds like in addition to studying you were also stressing out over it. In addition to what Cassie (0kai0) said, that stress will likely detract from your grades.

Overstudying is not good. You need to take breaks and make sure you don’t cram the night before (even though it may be hard to avoid). If you just keep studying while you’re half asleep, your brain isn’t really absorbing any of the information that you’re trying to comprehend. Make sure you have a good night’s rest and eat a really good, healthy breakfast the morning of your next exam :)

Your brain retains information much easier if you let it rest in between study sessions. Maybe, next time, give yourself two hours to study and in that two hours, take 2 or 3 ten minute breaks? You would also be surprised at how much a good nights sleep, before a test, helps!

I believe we over study with stress I think to if we don’t let it bother us so much it gets better and just eat right and get lots of rest it gets a lot better good luck

DO NOT WAIT UNTIL THE LAST MINUITE!!!!!!!