This study explores how mathematics teacher identity influences the adoption of dialogic teaching practices, which aim to engage students and deepen their understanding. Conducted in Johannesburg, South Africa, the research involved five highly qualified mathematics teachers: two newcomers with 2-5 years of experience and three experienced teachers with 25-30 years. Data were collected through lesson observations, video recordings, and interviews to examine the relationship between teacher knowledge and teacher identity in the implementation of dialogic teaching. The study is framed by the concept of "belonging," which includes three modes: engagement, alignment, and imagination. These modes provide a framework for understanding how teachers perceive their role in the classroom and their relationship to new teaching practices. The findings suggest that teacher knowledge alone does not fully explain the adoption of dialogic teaching. Instead, teacher identity—how teachers see themselves in relation to their teaching practices—plays a crucial role in their pedagogical choices.

The framework of belonging helps explain how teachers engage with dialogic teaching by aligning their practices with new methods and imagining their role in implementing them. Teachers who demonstrated strong knowledge and aligned their identity with dialogic teaching were more successful in integrating these practices. For example, one newcomer with strong subject matter knowledge effectively blended teacher- and learner-centred methods in his teaching. His sense of belonging to dialogic teaching allowed him to engage students actively, fostering participation and deeper understanding. Similarly, one experienced teacher, with strong knowledge of both subject matter and pedagogy, embraced dialogic teaching by aligning with and imagining its potential benefits. Her hybrid approach fostered student engagement and learning, illustrating how teacher knowledge and identity can work together to improve teaching practices. Conversely, teachers with weaker knowledge or a conflicted sense of identity faced difficulties in adopting dialogic teaching. One newcomer, with weak knowledge and a fragmented identity, employed some learner-centred methods but struggled to engage with students’ thinking, limiting his ability to implement dialogic practices effectively. An experienced teacher, attached to traditional, teacher-centred methods, struggled to adopt dialogic teaching due to resistance to new pedagogies and a conflicted identity. Similarly, another experienced teacher focused on procedures and rules, without fostering student interaction, due to limited pedagogical knowledge and a traditional teacher identity.

This study highlights the importance of teacher identity in adopting or resisting new pedagogical practices. Teachers who aligned their identity with dialogic teaching were more successful in engaging students and enhancing learning outcomes. The study emphasizes that both teacher knowledge and identity are essential in implementing effective teaching practices, particularly during curriculum changes. Strengthening both through professional development programs can better support teachers in adapting their practices, offering valuable insights for improving education.

Keywords: Teacher identity, Dialogic teaching, Mathematics education, Pedagogical practices, Teacher knowledge.