Dear Bill and Ron,

At the CBMS Forum earlier this month, I challenged participants to distinguish between statements widely held to be true, but actually myths, from those that are in fact true. I was not able to stay for the entire meeting, and after I left, during the discussion of the statements, Dick Askey asked for clarification about one of these statements: "How much mathematics a teacher knows is a good predictor of how effective he or she is." His question was a good one, for the way it was phrased was imprecise and therefore might be ambiguous. To make it clearer, I have made it more precise: T "The number of mathematics courses that a teacher has taken is a good predictor of how effective he or she will be."

As you know, I agree fervently that teachers' mathematical knowledge matters for the quality and effectiveness of their instruction. Content knowledge IS associated with more effective teaching. It is very important. The entire issue has to do with being more precise about what counts as the "content knowledge" that makes a difference. It is not the NUMBER of courses that a teacher takes, but rather the degree to which he or she knows the mathematics in ways that enable teaching. This is not pedagogy or pedagogical content knowledge, but a special quality and extent of mathematical knowledge. The NMP report importantly challenges the persistent equating of mathematics coursework with mathematical knowledge for teaching. We will never have teachers who know mathematics well enough if we do not acknowledge the special mathematical demands of teaching that require knowing mathematics differently (and more) than what is needed for many other mathematically-intensive careers or tasks.

Thanks for the opportunity to clarify the statement. I attach here the modified slides.


Updated Version of Deborah Ball's Presentation