'If it doesn't have an apex it's not a pyramid': Argumentation as a bridge to mathematical reasoning

Argumentation offers potential for students to engage in deep scientific learning, and to be enculturated into the practices of science. The need to make a claim, provide evidence, and justify the claim using evidence, serves to deepen students’ scientific reasoning. The research reported here introduces a model of argumentation to a class of Year 5 students through a geometry problem: “Can a pyramid have a scalene face?”. Observations suggest that many of the benefits of classroom argumentation practices in science may be apparent in mathematics education.