Ron Tzur is Professor of Mathematics Education at the University of Colorado Denver. His research has focused on children’s number and fraction knowledge, mathematics teacher development, and recently the use of a theory of the mind to study mathematical processes in the brain.

Hunt J. & Tzur R. (2017) Where is difference? Processes of mathematical remediation through a constructivist lens. The Journal of Mathematical Behavior 48: 62–76.

In this study, we challenge the deficit perspective on mathematical knowing and learning for children labeled as LD, focusing on their struggles not as a within student attribute, but rather as within teacher-learner interactions. We present two cases of fifth-grade students labeled LD as they interacted with a researcher-teacher during two constructivist-oriented teaching experiments designed to foster a concept of unit fraction. Data analysis revealed three main types of interactions, and how they changed over time, which seemed to support the students’ learning: Assess, Cause and Effect Reflection, and Comparison/Prediction Reflection. We thus argue for an intervention in interaction that occurs in the instructional process for students with LD, which should replace attempts to “fix” ‘deficiencies’ that we claim to contribute to disabling such students.

Steffe L. P. & Tzur R. (1994) Interaction and children’s mathematics. In: Ernest P. (ed.) Constructing mathematical knowledge: Epistemology and mathematics education. Falmer Press, London: 8–32. Fulltext at https://cepa.info/2103

In recent years, the social interaction involved in the construction of the mathematics of children has been brought into the foreground in order to sptcify its constructive aspects (Bauersfeld, 1988; Yackel, etc., 1990). One of the basic goals in our current teaching experiment is to analyse such social interaction in the context of children working on fractions in computer microworlds. In our analyses, however, we have found that social interaction does not provide a full account of children’s mathematical interaction. Children’s mathematical interaction also includes enactment or potential enactment of their operative mathematical schc:mes. Therefore, we conduct our analyses of children’s social interaction in the context of their mathematical interaction in our computer microworlds. We interpret and contrast the children’s mathematical interaction from the points of view of radical constructivism and of Soviet activity theory. We challenge what we believe is a common interpretation of learning in radical constructivism by those who approach learning from a social-cultural point of view. Renshaw (1992), for example, states that ‘In promulgating an active. constructive and creative view of learning,… the constructivists painted the learner in close-up as a solo-pia yer, a lone scientist, a solitary observer, a me:ming maker in a vacuum.’ In Renshaw’s interpretation, learning is viewed as being synonymous with construction in the absence of social interaction with other human beings. To those in mathematics education who use the teaching experiment methodology, this view of learning has always seemed strange because we emphasize social interaction as a primary means of engendering learning and of building models of children’s mathematical knowledge (Cobb and Steffe, 1983; Steffe, 1993).

Tzur R. (2014) Second-Order Models: A Theoretical Bridge to Practice, A Practical Bridge to Theory. Constructivist Foundations 9(3): 350–352. Fulltext at https://cepa.info/1090

Open peer commentary on the article “Constructivist Model Building: Empirical Examples From Mathematics Education” by Catherine Ulrich, Erik S. Tillema, Amy J. Hackenberg & Anderson Norton. Upshot: I address the value of Ulrich et al.’s distinction between three types of second-order models. I conclude that their work contributes to the theorizing of adaptive teaching on the basis of a constructivist stance on knowing and learning.