Background An adolescent's school is often the second most important place for his development and education after the home. However, reports highlight the recurrence of the use of violent discipline in schools. There are few school-based interventions that aim at reducing violence at school that have been implemented and evaluated in sub-Saharan Africa. To reduce violent disciplinary measures used at school, we aim to implement and evaluate the feasibility and efficacy of the preventative intervention Interaction Competencies with Children for Teachers (ICC-T). Methods/design The study will be conducted in six randomly selected districts of the Ankole region in southwestern Uganda. We shall randomly select two mixed-day secondary schools from each district that fulfill our inclusion criteria. Schools will be randomly assigned to the intervention condition, where ICC-T will be implemented, and control schools (no intervention). Sixty students between the ages of 12 and 17 years and at least 15 teachers per school will be included in the trial. We aim to collect pre-assessment data directly before the intervention (t1) and 3 months after the intervention (t2) in both intervention and control schools. Using self-administered questionnaires, we will measure students’ exposure to violence using the Conflict Tactics Scale (CTS), their psychological well-being using the Strengths and Difficulties Questionnaire (SDQ), and teachers’ positive attitudes towards violent disciplining and teachers’ use of violent disciplinary methods (CTS). The implementation feasibility of ICC-T in the cultural context of southwestern Uganda will be assessed with purpose-built measures that follow the guidelines for feasibility studies assessing the demand, applicability, acceptability, and integration of core elements in the daily work. Discussion The proposed study will allow us to test the feasibility and efficacy of a preventative intervention seeking to reduce violent disciplinary measures in school settings using a scientifically rigorous design. The proposed study provides the opportunity to contribute to the attainment of goal number 16.2 of the United Nations’ Sustainable Development Agenda 2015–2030, which aspires to end all forms of violence against children. Trial registration ClinicalTrials.gov, NCT03051854. Registered on 14 February 2017. Electronic supplementary material The online version of this article (10.1186/s13063-018-2827-9) contains supplementary material, which is available to authorized users.