Okay this is very funny, but there's a good point here.
grades shouldn't be as important as they are, learning should be the most important part of school. So basically we just spend six cruel hours of our lives almost every single day, and then when tests or other stuff pop up they say "Get an A, that's all we care about" so then when you do get a relatively good grade, you immediately move on and forget what you learned. The school system is stupid, and is only about getting a good grade.