If teachers were just teaching concepts and facts then the principal would be right. You either understand what was being taught or you don't and there's really no middle ground. In fact, if you don't there should be some sort of discussion as to why so you can get back onto the same page as everyone else.

But most teachers aren't just teaching their special little field and most are certainly not just grading you on it. When I was in school we were also graded on having our work done on time, playing well with other in group scenarios, and other little life lessons. Those are things you can grade on a scale of A-F.

So if nothing else, it would seem more reasonable to almost need to split the grades into pass/fail for comprehension and scale for everything else. At least then you could truly see where someone excels and where they need improvement.

At least that's my take on it.

My post was not in reference to women not being interested in dating, but not having 'relief' for biological urges. As a guy, I'd find it hard to believe that if you're not getting laid that you're also not masterbating, which is pretty much what you said. Unless...
1. You're a woman: My point with this was the fact you have no balls.
2. Your balls are locked away somewhere: Again, no balls.
3. You're engaging in some rather unhealthy sexual activities: Meaning you are getting sexual relief, but ouside of the confines of marriage, dating, or even being interested in dating. This could be construed as unhealthy. At least as supposedly unhealthy as masterbation is.

So you're not "married/dating/interestedindating" and you think that masterbation is unhealthy. So either you're a woman, your balls are locked away somewhere, or you're engaging in some rather unhealthy sexual activities yourself. Whichever it is, good luck with all that!