(I've taught science/math for past 15 years): In primary and secondary education any sort of curving is (and should be) looked down upon if not outright disallowed. If the average student scores an 94% on a test it should either be considered that the students learned the material or the teacher wrote too easy of a test. To tell a student that their 92% is worth a C because of how well other students did is poor practice because it shouldn't matter how well those students do - all that matters is how well the tested student meets the desired outcomes. All of my courses are graded on a pure percentage basis and if I write a poor exam (too easy) I record that for the next year; if I write too hard of an exam I either allow some form of a retake (it was a fair test but students didn't hold up their end of the learning bargain) or I scale the grades up (I wrote a poor exam that was too hard).

You complain about how students are taught by telling them the problems and answers. I've taught for the past 13 years in science and as soon as you do any reasonable inquiry you get complaints from both student and parents.. HE WON'T TELL MY SON THE ANSWER. Damned if you don't...