National Council on Teacher Quality:

It’s never been done.
We’re going to do it.
Every year across the country, around a quarter of a million people enter the teaching profession. Almost all of them are prepared in the nation’s schools of education. If the country is serious about bending upward the curve of its students’ stagnant academic performance, improving the preparation of new teachers would seem to be a crucial step. And yet, very little is known about the quality of teacher preparation programs–their selectivity, the content and pedagogical knowledge that they demand that their teacher candidates master, or how well they prepare candidates for the rigors of the classroom. Without such knowledge, people thinking about becoming teachers can’t make informed choices about where to get trained, district superintendents and principals don’t know where to look for well-prepared teachers, and policymakers lack the means to sanction poorly performing education schools.