Dialogic approaches based on active student participation, open, respectful discussion, exploring and critiquing different perspectives are increasingly found to support student learning. However, the specific productive forms of teacher-student interaction have rarely been studied systematically. A recent large-scale project explored the relationship between dialogic forms of interaction and learning outcomes for students aged 10-11 in primary school classrooms in England. This follow-up study built on the dataset and outcomes of that study. The objective here was to generate insights into the forms of interaction observable within classes achieving higher and lower learning gains in English and mathematics. Sociocultural discourse analysis combined in-depth qualitative analysis with corpus linguistics methods. The specific forms of dialogue emerging in the earlier study as most productive for learning from turn-by-turn coding and whole-lesson ratings were analysed in more depth. The findings offer rich illustrations of how the productive features are manifested in authentic classroom practice. The outcomes contribute to our understanding of which specific forms of teacher-student dialogue support learning, and how teachers may actively promote these.