The aim of this work was to design and implement an effective hybridisation of two pedagogical models that would serve to overcome gender-related barriers to participation in games, based on a co-educational intervention and paying a special attention on the boys' influence for the girls' participation. First, we describe the process of creating the hybrid pedagogical model combining the activist approach (Oliver & Kirk [2015]. "Girls, gender and physical education: An activist approach." Routledge.) and teaching games for understanding (Bunker & Thorpe [1982]. A model for the teaching of games in secondary schools. "Bulletin of Physical Education," 18, 5-8). We then present its 11-week implementation in a physical education class of 20 pupils in the 5th grade of primary school. Finally, we analysed the achievement of the objectives established, whereby the qualitative information gathered from interviews, focus groups, and the participants' observation diaries, is complemented with the quantitative evaluation of game performance. The whole group worked together to modify our actions, allowing the girls to participate more actively, what reflected a significant improvement of the girls' involvement in the game.