<p>Engaging students in substantive thinking in mathematics can be challenging for teachers to achieve. Institutional norms and teacher-centred approaches do little to mitigate the occurrence of non-thinking student behaviours, thereby requiring the adoption of different teaching practices that are likely to optimise mathematical thinking and active engagement in mathematics lessons. This adoption often requires changes in teachers’ practices which can only be achieved and subsequently sustained by exposure to alternative approaches often through professional learning. Engagement by teachers in active learning that targets subject content and student learning, and having the opportunity to implement and reflect on the impact of adopted practices is likely to result in sustained changes to practice and development of professional growth. This paper reports on a case study conducted with a teacher who was supported to implement evidence-based practices designed to facilitate students’ thinking in mathematics lessons. Following collection of baseline data that showed her students were not demonstrating evidence of mathematical thinking in mathematics lessons, the teacher, with support of a mathematics education researcher, implemented teaching approaches designed to engage students in mathematical thinking. The findings indicated the teaching approaches were effective in engaging students in mathematics and reducing non-thinking behaviours. Furthermore, the teacher’s exposure to a knowledgeable other who supported her with professional experimentation, and evidence of salient outcomes, led to shifts in her knowledge and beliefs and subsequently to changes in the teacher’s practice and professional growth. The study has implications for school leaders and teachers who are looking to make sustained changes to the way that mathematics is taught in schools based on evidence-informed teaching approaches.</p>