Lessons learnt from the COVID-19 pandemic highlight the importance of preparing future educators to deliver effective instruction in both face-to-face and fully online environments. We thus explore the use of lesson recordings from synchronous online mathematics classes, supported by visual learning analytics (VLA), as innovative research and educational resources in teacher education. Focusing on a high-achieving pre-service teacher (PST), this case study investigates how these resources facilitate exploration and reflection on teaching strategies. Our findings suggest that the PST found VLA to be instrumental in understanding teaching practices and classroom interactions. Most importantly, he was able to recognise good practices in synchronous online lessons, including questioning techniques and scaffolding strategies. Drawing on his own learning and tutoring experiences, he offered valuable suggestions for instructional improvement, such as using dynamic mathematics software and employing online collaborative tools for real-time student feedback. The contribution of this study is thus twofold. First, it contributes to the ongoing discourse on effective approaches to teacher training. Second, it identifies effective practices from the PST’s perspective to inform future synchronous online mathematics instruction.