Studies of primary education within the UK have shown that small groups can feature within classrooms; however, equivalent research within secondary education remains scarce. Research has established effective group work approaches, yet secondary teachers may encounter difficulties employing approaches tied to parameters embedded within primary education. This problem is compounded as minor adjustments to the conditions surrounding group work are known to have consequences for its efficacy within classrooms. This paper reports naturalistic systematic observation of group work practice within 23 science and English secondary classrooms in Scotland. Pupils completed tasks according to whether they were situated within group work or conventional classes. Forms of dialogue known to be conducive to learning were prevalent whilst pupils worked in groups. The change in pupils' behaviours does not appear to stem from the content of teachers' talk. Teachers' behaviour suggested they approach small groups as smaller structures equivalent to a whole-class set-up. (Contains 1 figure, 4 tables and 4 notes.)