(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...

We're talking from two different sides of the issue, in addition to the fact that I'm talking about secondary education for which I have over 10 years of experience in addition to Ed credentials and graduate work in education.

You seem to talk about what you would like (all teachers to have a math ed degree, or that two teachers be assigned to a course), whereas I'm talking about the reality that:

a.) people who teach math 80% of the time have no better than a BA in math which means that not only do they have limited experience in upper level mathematics but their knowledge and application of mathematics is limited in addition to a basic and weak background in science

b.) even when people get a BA in math and then get a MA in teaching - the methods courses are weak and ineffective, barely providing what they need to teach the content let alone applications.

c.) schools cannot afford to have two teachers assigned to a single course, let alone teachers that are in high demand like math and physics as there just aren't enough qualified candidates out there.

d.) you underestimate the benefit of higher level mathematics when teaching. I would say that for secondary education linear algebra and high level calc are not enough - rather I would prefer the teacher have those courses in addition to upper division applied math courses in modern topics of science. I have seen numerous "math ed" teachers struggle with applications of mathematics beyond what is provided in the text - often teaching incorrect science or doing poor methods in modeling.