When the people of defend the lack of education studies in America. They say things like, "Every child is unique" to defend the fact that they are unwilling to study education, its methods, and change. They say things like, "the environment the kid grows up in is to variable to study."
The American school system have probably one of the largest control samples in the entire world. Every single child comes to school and learn basically the same thing. If you cannot put together a large study from that, you are never going to get ahead.
I am not suggesting the research educators start large. In fact, I think they should start small, with many different test groups from many different areas. That process will probably yield a few ideas, that are worth pursing at a larger level. You could have a tiered education research cycle for teaching methods. If it works on a small group, it could then be tried on a larger group, and if it worked on that group, try it on a larger group.
Of course I would be immediately against this idea, if it were suggested that the government take over this task. I would prefer that an education company try my idea.
This is not the critics individual teachers. In fact that is their job to deal with the differences that each kid has and get them to learn some how. On a large level those differences should start to melt away, and you should start to see trends on what works and what does not work. That is where the research come in.