Dr. Eric Knuth, University of Wisconsin

In this session, results will be presented from a research project that seeks to understand the development of middle school students' competencies in justifying and proving. The primary focus of the session will be on the nature of the justifications students produce for their solutions to a variety of mathematics tasks. Data from written assessment items and interviews will be used to illustrate the results. Implications regarding instructional practices and curricular designs necessary to support the development of students' competencies in justifying and proving will also be discussed.