Our work investigated how six primary school students used a non-traditional method for adding and subtracting: the ABN method, a Spanish acronym for Open (method) Based on Numbers. Commognitive theory [Sfard, A. 2008. "Thinking as Communicating: Human Development, the Growth of Discourses, and Mathematizing." New York: Cambridge…

This observational study used data from 270 second-grade students to investigate the association between students' strategy use for multidigit addition and subtraction and their mathematics achievement. Based on strategies they used during a mathematics interview, students were classified into the following strategy groups: (a) standard algorithm,…

Children are asked to describe the subtraction process or to describe a context in which subtraction may be used. (JLH)

This study assessed the extent to which procedurally proficient children (N=34) construct the part/whole logical structure that underlies the borrowing algorithm in subtraction. Results indicate that an understanding of the part/whole logic of number may be necessary to understand place value and borrowing. (TJH)