The aim was to explore school nurses' health dialogues with pupils regarding physical activity. A descriptive explorative qualitative design based on video recordings of 15 nurses performing 24 ordinary real-life health visits with pupils aged 10,14 and 16 years was used to accomplish this. Audio files from the video recordings were transcribed verbatim and subjected to qualitative content analysis. The results showed that the school nurses created a flow and kept the conversation going to enable the progress of the health dialogue about physical activity. To gain the pupils' trust, the nurses used social talk and gave positive feedback. By assessing information about the pupils' activity the nurses created an overview and then, based on this overview, tried to create a potential for change in physical activity.