Improving the well‐being of children has been widely discussed, yet research‐exploring strategies aimed at improving this in school‐based settings is still an emerging field of research. This mixed methods study investigated the impact of a singing intervention on the subjective well‐being of a class of 27 children aged 8–9. Over the course of 2 weeks, the class took part in 20 minutes of daily group singing with a focus on learning popular music that they chose. The sessions were delivered by a generalist primary teacher who had previously worked as a music specialist. In measuring children's subjective well‐being with emphasis on life satisfaction, the ‘Student's Life Satisfaction Scale’ was administered to the children pre‐ and post‐intervention. Of the 27 children, four (identified as disadvantaged) were interviewed as part of a focus group at the end of the intervention and questions centred around the children's opinions and enjoyment of the intervention. Results indicated that there was a much lower proportion of children with low subjective well‐being scores after the intervention than before the intervention (as measured by the SLSS questionnaire). Analysis of the Likert scale data showed a ‘medium’ (d = 0.5) effect size. Thematic analysis of the focus group revealed that singing had a broadly positive effect on the well‐being of those children, which is consistent with findings found in similar trials involving adults. Links to the theoretical framework of ‘flow’ by Csikszentmihalhi (1975) are drawn, alongside the PERMA well‐being framework model (Seligman, 2012) to help explain the effects of being engrossed in an enjoyable activity such as group singing and how this in turn can impact subjective well‐being.