1Developing Measures of Teachers ’ Mathematics Knowledge for Teaching

In this article, we discuss efforts to design and empirically test measures of teachers’ content knowledge for teaching elementary mathematics. We begin by reviewing the literature on teacher knowledge, taking special note of how scholars have organized such knowledge. Next we describe survey items we wrote to represent knowledge for teaching mathematics and results from factor analysis and scaling work with these items. We found that teachers ’ knowledge for teaching elementary mathematics is multidimensional, and includes knowledge of various mathematical topics (e.g., number and operations, algebra) and domains (e.g., knowledge of content; knowledge of students and content). The constructs indicated by factor analysis form psychometrically acceptable scales. 3In the past two decades, teachers ’ knowledge of mathematics has become an object of concern. New theoretical and empirical insights into the work of teaching (e.g., Shulman, 1986, 1987; Wilson, Shulman, & Richert, 1987) have spurred greater attention to the role played by such knowledge in teacher education and the quality of teaching itself (e.g., NCTAF, 1996). Other studies have documented the mean and variation in teachers