here is a positive relationship between children’s movement competence and physical activity, with a further relationship established between physical activity and childhood obesity. The Movement Oriented Games Based Assessment (MOGBA) is a delivery and assessment intervention designed to improve children’s complex movement skills, based on principles of motor development and assessment theories. MOGBA aims to improve children’s movement competence, physical fitness and self-perceptions (physical and game) and increase children’s moderate-to-vigorous physical activity (MVPA). MOGBA is to be used in the ‘Made to Play’ initiative, involving 105 sports and activity programs across 21 countries, involving over 25 million children. A multi-site cluster randomized controlled trial will take place across three global sites (UK, Ireland and Australia). Each site will recruit eight primary schools (four experiment, four control) with each school providing two separate classes of children from age ranges 8–12 years (Site n = ~300, total n = 904). After baseline assessments, schools will be randomly allocated to an experimental or wait-list control group. Following two half-day workshops, trained facilitators will deliver the MOGBA intervention for 9 weeks. The main intervention components include delivery of 14 games-based activities with associated assessments of children’s movement and differentiation to meet children’s needs by manipulating space, effort and relationships. The primary outcome of the trial is to improve children’s’ movement competence (The Dragon Challenge), with secondary outcomes of improving children’s’ in-activity and leisure-time MVPA (5-day accelerometer), physical fitness (standing long jump and push ups) and self-perceptions (physical and game). Data will be analysed using multilevel modelling approaches. The MOGBA intervention has been designed to improve children’s movement competence and scalable interventions based on MOGBA could be applied across programs within the Made to Play initiative, globally. The trial is registered at the Australia New Zealand Clinical Trial Registry (ACTRN12619001320145p, 27 Sep 2019).