Abstract/Description: Past research on students' understanding of the equal sign has focused largely on two meanings: operational and relational. In this poster, we introduce two additional meanings for the equal sign and describe the findings of a textual analysis of four middle school curricula that shows all four meanings are used in secondary mathematics. Based on our findings, we conclude that growth in expert use of the equal sign is characterized by the adoption of additional meanings and a gradual increase in one's ability to use the contexts in which equations are embedded to determine which meanings of the equal sign are being used. We present a model of an expert conception of the equal sign that consists of three fundamental understandings regarding the meanings for and uses of the equal sign.
Presenters: Dan Siebert and Emeline Thygerson, Brigham Young University