Gesture as data for a phenomenographic analysis of mathematical conceptions

•Interpretation included in phenomenographic analysis.•Gesture complements, supplements and sometimes contradicts utterances.•Without her pointing Lisa's words seemed to be nonsense.•Annie said “I think it will go like that”. We needed to see her gesture to complete this statement.

This paper reports on a phenomenographic investigation for which both participant utterances and their gestures were analysed in order for researchers to gain insight into their understanding of the concept of rate. Video-recordings were made of twenty interviews with Year 10 students. Detailed analysis, of both the sound and images, illuminated the meaning of rate-related gestures. Findings indicate that students often use the symbols and metaphors of gesture to complement, supplement or even contradict verbal descriptions. This study demonstrates, in one setting, the efficacy of phenomenography, with attention not only to participants’ words but also their gestures, to explore mathematical conceptions.