Most teachers I know weren't Science/Math majors, they were Liberal Arts majors and would not have stood a chance in a engineering program.
Not sure I agree. What kind of "methods and materials" are you thinking of? IMO, teaching should be consistent across a school district so as to reduce duplication of effort and/or confusion when kids change from one class to the next.
Aaron Z
There is a perennial shortage of math and science teachers. I picked those fields to illustrate my point. Most college students would not stand a chance in any rigorous engineering program, so teachers are no different in that regard. What we want teachers to know, in addition to subject matter, is the science of how learning takes place, teaching methods that recognize that science, some basic understanding of psychology, and a good grounding in sociology. I bet most engineering majors would not be interested in those things.
On pay scales, teachers are generally paid based on degrees earned, credit hours toward or beyond a degree, and longevity. Generally, no distinction is made for subject matter. The Athletic Director of a large school often makes more than the teachers, for an example of community priorities.
On materials, if a biology teacher was prohibited from teaching evolution, how is that going to work out? No matter your personal view, you have to see that as an artificial limiting of education and knowledge. If a history teacher cannot include some of the things omitted from standard texts, a text the teacher has to use and often had no input in its selection, we are not rewarding expertise and depth of knowledge. You cannot put smart people in a little box and expect good things. Businesses don't do that. I agree there has to be some consistency in a core curriculum, but using up all of a teacher's class time to meet that core is ignoring what they as individuals can bring to the table.
On methods, the cheating scandals around standardized testing speak for themselves. Teaching to a test is not a valid method, capable teachers know that but certainly aren't going to be given the leeway to opt out of the nonsense. No, instead we reward those who do not value intellectual integrity and cheat to succeed.
Two important things teachers can inspire in students is a thirst for knowledge and improving a student's ability to learn. Those are difficult or impossible to measure by testing, but they are crucial for the student.