Implications for Children With Mathematical Disabilities

Drawing on various approaches to the study of mathematics learning, Gersten, Jordan, and Flojo (in this issue) explore the implications of this research for identifying children at risk for developing mathematical disabilities. One of the key topics Gersten et al. consider in their review is that of “number sense. ” I expand on their preliminary effort by examining in detail the diverse set of components pur-ported to be encompassed by this construct. My analysis reveals some major differences between the ways in which number sense is defined in the mathematical cognition literature and its definition in the literature in mathematics education. I also present recent em-pirical evidence and theoretical perspectives bearing on the importance of measuring the speed of making magnitude comparisons. Finally, I discuss how differing conceptions of number sense inform the issue of whether and to what extent it may be teachable. Gersten, Jordan, and Flojo (inthis issue) judiciously reviewand appraise relevant empiri-cal evidence and theoretical perspec-tives pertaining to issues of both the early identification of mathematical disabilities (MD) and their remedia-tion. Among other topics they cover in their incisive treatment of several per