The Instructor's Important Role In Supporting Mathematical Arguments in a K-5 Mathematics Specialist Program

Joy Whitenack, Virginia Commonwealth University
Laurie O. Cavey, Boise State University
Aimee Ellington, Virginia Commonwealth University

Abstract

In this presentation, we use examples from a one lesson taken from an algebra course for K-5 mathematics specialists to illustrate the instructor’s role in supporting argumentation. Krummheuer’s (1995) theory of ethnography was a particularly useful methodological tool for tracing the argument that unfolded during the discussion. As part of this interpretive model, we assume that normative ways of making mathematical arguments are socially accomplished, although individuals contribute to and participate in these arguments in different ways. Preliminary findings suggest that as the instructor highlighted teachers’ explanations he and the teachers established mathematical arguments. In some cases the instructor provided warrants or backings that remained implicit or omitted (cf. Yackel, 2002). In other instances the instructor coordinated different explanations to substantiate or validate the arguments that emerged. By doing so, he made it possible for teachers to engage in making more formal arguments.