ObjectiveMental health disorders affect many children in South Africa, where vulnerability is high, and treatment is limited. We sought to determine the feasibility and acceptability of a universally delivered classroom‐based programme for the promotion of mental health in young adolescents.MethodWe pilot tested an 8 session, cognitive‐behavioural therapy‐based programme, 4 Steps To My Future (4STMF) in two schools. Participants were grade 5 learners (n = 222; Meanage = 10.62 (Standard deviation = 0.69)). 4STMF was delivered in class time by trained psychology postgraduates. Feasibility (rates of parental opt‐out, child assent, assessment completion at baseline and follow‐up, programme completion, session attendance and programme fidelity), acceptability (teacher feedback and focus groups with learners), as well as demographic data and data on a battery of a psychological measures were collected at baseline, postintervention and at one‐month follow‐up.ResultsMost eligible learners at both schools agreed to participate (85% – school 1; 91% – school 2) with more than 80% completing postintervention measures. Learner session attendance and programme fidelity were high. Teachers rated facilitators highly on confidence, preparedness, enthusiasm and classroom management and observed children to be enjoying the programme. Focus group data suggest that learners liked the programme, could recall the content and had shared some of the content with their family. An exploratory analysis of outcomes showed significant pre–post differences on self‐esteem at school 1 and on emotion regulation at school 1 and school 2, maintained at follow‐up.ConclusionsThis pilot study has shown that 4STMF can acceptably and feasibly be delivered, at classroom level, as a universal school‐based prevention programme to young adolescent learners in South African primary schools. The programme could fit in with school context, could be delivered by nonspecialists, showed significant improvements on self‐esteem and emotion regulation and was liked by the learners.