The aim of this study was to evaluate the effectiveness of the State of Mind (SoM) wellbeing programme, a community and school-based intervention for young people aged 13–16 in Wales, developed by the charity “Platfform”. This research sought to understand both the impact of the programme on self-reported wellbeing and the lived experiences of young people who participated.

A mixed-methods approach was adopted. The quantitative analysis utilised secondary data comprising of 494 school pupils’ scores on the Warwick‑Edinburgh Mental Wellbeing Scale (WEMWBS). Combined non-parametric and Bayesian approaches were used to assess changes in wellbeing from baseline to post intervention. Qualitative data was collected through semi-structured interviews with nine young people. A reflexive thematic analysis of this data was conducted to explore participants’ perspectives of the programme.

There was a statistically significant improvement in wellbeing scores following participation in the programme. Qualitative findings indicated that participants experienced positive change, including improved emotional awareness, coping, and relationships. Supportive staff, relatable content, and peer connection facilitated these outcomes, though areas for improvement were also noted.

Findings suggest the State of Mind programme positively supports young people’s mental wellbeing. Participants valued its supportive, relatable approach and felt better equipped to manage emotions. Suggested refinements, such as deeper topic coverage and extended delivery, may enhance its impact and sustainability.