The Number Line as a Representation of Decimal Numbers: A Research with Sixth Grade Students

Abstract

One of the aims of mathematics instruction is to achieve the understanding of mathematical concepts through the development of rich and well organized cognitive representations (Goldin, 1998; NCTM, 2000; DeWindt-King, & Goldin, 2003). In this study the term representation is interpreted as the tool used for representing mathematical ideas such as tables, equations and graphs (Confrey & Smith, 1991). The first aim of this study is to investigate 12 year old students' understanding of addition of decimal numbers. Second, to explore the way these students understand and utilize the representations of decimal numbers as different concepts - modularization - or as different expressions of the same concept. The third aim of the study is to investigate which modes of representation of decimal numbers are the most difficult ones. Finally, the study is dealing with the differences in students' achievements concerning the issue addressed by the different exercises - concept and addition of decimals. For complete proceedings, see ED489538.]