Recently, there have been calls to create some kind of accreditation for Judaic studies teachers in day schools (see, for example, here). I have my doubts. Even if accreditation was a proven tool for general education, what institutional body could provide a certification for teachers that would be acceptable and meaningful for a plurality of even Orthodox schools? Could there possibly be consensus on what is important?
Be that as it may, a recent study (short summary here), conducted by master teachers in conversation with other teachers, suggests that much of the research on teacher accreditation is beside the point. That research correlates teacher certification with standardized tests, and, as everybody knows (or ought to know), high standardized test scores are not the same thing as actual education. Instead, the study claims, we need much more robust categories to describe what makes a good teacher, and those categories would inevitably change the way certification programs are structured.
Recently, a post on Lookjed also cited this report in the Wall Street Journal, also questioning the value of teacher certification.