Designing and Evaluating a Classroom-Based Mental Health Programme for Adolescents.

This is a mixed-methods feasibility study to evaluate the delivery, feasibility and acceptability of a universal psychoeducational programme. The intervention aims to build students' mental-health literacy and confidence in recognising and responding to distress. The programme is educational in focus; it is not designed to diagnose, treat symptoms, or identify individuals at clinical risk. The trial uses a non-randomised parallel-group design in which participating secondary schools are allocated to either the intervention arm or a teaching-as-usual control arm. The intervention comprises four structured classroom sessions delivered within the normal school timetable. Session content includes: (1) understanding mental health and the stress response; (2) understanding unusual sensory experiences and psychosis; (3) understanding stigma and media influences; and (4) understanding thoughts and feelings using cognitive behavioural therapy-informed coping strategies. Sessions use multimedia materials, group discussion, and workbook activities. All content was co-designed with individuals with lived experience of psychosis, mental health professionals, and teachers. Students in the control arm will continue with teaching-as-usual during data collection and will be offered the intervention after the study follow-up period (waitlist). Quantitive data will be collected at multiple timepoints to assess feasibility including recruitment, retention, data completeness, adherence to planned session components. Students will complete baseline, post intervention and one month follow up questionnaires, as well as brief surveys and reflections after each session to capture engagement and acceptability. Pre-post changes in key outcomes will be explored descriptively using repeated measures approaches to examine patterns of change and to estimate variance for planning a future definitive trial, where data completeness permits. Psychotic-like experiences, emotional and behavioural functioning, and help-seeking intentions will be assessed using validated self-report tools. These include the Prodromal Questionnaire-16 (PQ-16), the Strengths and Difficulties Questionnaire (SDQ) and the Mental Help Seeking Intention Scale (MHSIS). A qualitative component, consisting of semi-structured interviews with a subset of participants will explore experiences of the programme, perceived relevance, acceptability and suggestions for refinement. The primary purpose of this study is feasibility rather than efficacy. Findings will inform decisions about progression to a future trial, including necessary refinements to content, delivery and evaluation procedures.