Distinctions between argumentation and explanation by secondary-school mathematics teachers

Argumentation and explanation are relevant discourse practices in the mathematics classroom, and their success is determined by how teachers describe, distinguish, and foster their enactment. This study explores distinctions made by secondary-school mathematics teachers between these discourse practices. The theoretical framework approaches argumentation and explanation through an interpretation of the Linguistic–Normative Model of Argumentation (LNMA) and its grounding in Speech Act Theory. Hybrid deductive and inductive thematic analysis methods were employed to characterise the definitions, essential conditions, and differences between both practices in individual responses by ten secondary-school mathematics teachers to a questionnaire. The results reveal that teachers describe and demarcate distinctions between argumentation and explanation by characterising them as epistemic–mathematical, enunciative–informative, and instructional practices, and by attributing to them epistemic-applicative, informative, and cognitive goals. Finally, conclusions are drawn regarding: (i) the role of describing discourse practices in facilitating their distinction, (ii) the qualities of teachers’ descriptions and distinctions between the practices, and (iii) the limited alignment between teachers’ distinctions and the theoretical perspective considered.