Investigating curricular effect on the teaching and learning of mathematics in a cultural context: Theoretical and methodological considerations

► We discuss curricular effects on mathematics teaching/learning in cultural contexts. ► We provide a theoretical/methodological context for two longitudinal projects. ► We raise seven issues related to the articles in this special issue. This first article of the special issue presents theoretical and methodological considerations about longitudinally investigating curricular effects on the teaching and learning of mathematics in a cultural context. In particular, in this article, we discuss seven issues related to the investigation of curricular effects on the teaching and learning of mathematics: (1) the need to investigate longitudinally the effects of curriculum, (2) the nature of the reform and non-reform curricula, (3) multiple representations of curriculum use, (4) assessment of classroom instruction, (5) student diversity and achievement gaps, (6) multiple measures of student mathematics achievement, and (7) multi-level analysis of student achievement data. This article not only serves as an introduction to the special issue, but most importantly, also provides a theoretical and methodological context for the two longitudinal projects.