This study offers a close look at the discourse in two 8th grade mathematics classrooms using a reform-oriented mathematics curriculum in the US. The teachers who are the focus of the study have many attributes in common (eg. similar academic backgrounds and professional development activities, same school, same curriculum and a similar enthusiasm for it), yet teach differently. Drawing from a larger database of classroom observations and teacher interviews, I describe and analyse classroom transcripts using both a more general distinction between discussion and recitation (Barnes, 1976; Nystrand, 1995) and the idea of a "mathematical discussion" (Pirie & Schwarzenberger, 1988). I look closely at the classroom interactions during student's introduction to solving quadratic functions and argue that differences appear in the classroom discourse. For example, both teachers controlled aspects of the classroom exploration, but one teacher controlled the turn and topic (Griffin & Mehan, 1981), while the other teacher controlled the "common knowledge" (Edwards & Mercer, 1987) in the classroom. In terms of mathematical statements, the latter teacher also allowed students to make both "reflective" and "operational" statements (Pirie & Schwarzenberger, 1988). In contrast, the first teacher allowed students to mainly make "operational statements" and saved the "reflective statements" for himself. The main difference in the classrooms appeared in the roles the teachers and students took on, which may have affected the epistemology each teacher advocated.