The purpose of this study was to find out how teachers use questions in classroom discourse to scaffold student thinking and help students construct scientific knowledge. The study was conducted in large-class settings where the medium of instruction was English although the students were non-native speakers of the language. Six teachers teaching grade 7 science classes from four schools participated in the study. Thirty-six lessons covering a range of topics were observed across a variety of lesson structures such as expository teaching, whole-class discussions, and laboratory work. The lessons were audiotaped and videotaped. Verbal transcripts of classroom discourse were analyzed interpretively. Particular attention was paid to questioning exchanges that stimulated productive thinking in students, as manifested by their verbal responses. A framework was developed that included four questioning approaches adopted by the teachers. This included Socratic questioning, verbal jigsaw, semantic tapestry, and framing. This paper describes these various questioning approaches, their features, and the conditions under which they were used. It also discusses the implications of these approaches for instructional practice. The findings from this study have potential in translating research insights into practical advice for teachers regarding tactical moves in classroom discourse, and provide guidelines for teachers to increase their repertoire of questioning skills. © 2007 Wiley Periodicals, Inc. J Res Sci Teach 44: 815–843, 2007