This article extends the notion of "knowledge at the mathematical horizon" or "horizon knowledge" introduced by Ball and colleagues as a part of teachers' subject matter knowledge. Our focus is on teachers' mathematical knowledge beyond the school curriculum, that is, on mathematics learnt during undergraduate college or university studies. We…

I propose that attending how symbolizing activity functions for teachers and students helps to characterize student-teacher communication, and allows for an investigation of how symbolizing activity contributes to learning. I begin this discussion by articulating four ideas-schemes, symbolizing activity, communication, and learning. Then I propose…

This paper analyses how the mathematical knowledge needed by a teacher has been described by several mathematics educators, all based on Shulman's notions of Subject Matter Knowledge and Pedagogical Content Knowledge. In particular, it looks at the notion of Mathematics Knowledge for Teaching, as elaborated by Ball and her research group. It then…

This paper first reports on the methodology of a study of teacher knowledge for statistics, conducted in a classroom at the primary school level. The methodology included videotaping of a sequence of lessons that involved students in investigating multivariate data sets, followed up by audiotaped interviews with each teacher. These stimulated…

Examples play a central role in mathematics learning and teaching. Although they involve specific situations, their purpose is to exemplify more general mathematical principles. A critical task of teaching, therefore, is to choose appropriate examples and implement them in pedagogically productive ways. This study considers the examples used by…

This paper explores secondary teachers' views on the role of visualisation in the justification of a claim in the mathematics classroom and how these views could influence instruction. We engaged 91 teachers with tasks that invited them to: reflect on/solve a mathematical problem; examine flawed (fictional) student solutions; and, describe, in…

We report on a two-year "concept study" in which a cohort of middle school teachers collectively deconstructed and reconstructed the concept of multiplication. Defining concept study as a collaborative structure through which mathematics educators identify, interpret, interrogate, invent, and elaborate images, metaphors, analogies, examples,…

In this paper we explore the growth of understanding of a group of preservice teachers, and their instructor, as they work collectively together on what we describe as a "mathematics for teaching" task. Through drawing on elements of improvisational theory, in particular the notion of the "better idea," we analyse how the preservice teachers'…

The ability of mathematics teachers to decompress mathematics and to move between representations are two key features of mathematical knowledge that is usable for teaching. This article reports on four pre-service secondary mathematics teachers learning the mathematics of annuities. In working with spreadsheets students began to make sense of…

Mathematical knowledge used in teaching has attracted the interest of many researchers, but was mainly explored considering teaching at the elementary school level. This paper attends to mathematical knowledge used in teaching at the University level. We present a story about a student suggesting reconsideration of Cantor's diagonal method and the…

We introduce Lesson Play as an imaginary interaction between teacher and students presented in a form of a dialogue or play. We suggest that lesson plays are a valuable professional development tool in preparing for teaching that can be juxtaposed with, or used as a replacement for, traditional lesson planning. The article begins with an…

Critical mathematics education cannot be translated into principles. Aims to search for a working philosophy of mathematics for critical mathematics education. Concludes that aporism attempts to consider mathematics in its social, cultural, and political complexities, and to express uncertainties about mathematics' possible role as an educational…

Describes a study which took place in a grade 9 classroom that consisted of five groups with 3-5 pupils in a group. Pupils were required to calculate the areas of a number of shapes on a geoboard. Concludes that a teacher working with pupils in small groups brings new challenges for mathematics teachers. (Contains 11 references.) (ASK)

Addresses the concept of mathematical definition as well as the definitions of different mathematics concepts. Focuses on the possibility of defining a mathematical concept in several ways based on logical relationships between different mathematical statements related to the concept. The choice of one of these statements as definitional plays a…

Discusses the elements of an interactional theory concerning content-related learning in classroom situations. Clarifies the concept of culture and outlines the narrative character of the reconstructed classroom culture. Presents empirical results to create elements of a theory of interaction of content-related learning. (Contains 37 references.)…