CHILD-UP (Children Hybrid Integration: Learning Dialogue as a way of Upgrading Policies of Participation) addressed the issue of inclusion of children with migrant background in the European education system through an innovative perspective, based on the concepts of children agency and hybrid integration. This project put children’s agency at the centre. Agency means that children select and combine, in personal and original way, cultural elements of originating country and hosting country, local and global perspectives. The project proposes a view of hybrid integration as cultural combination, based on both native and migrant children’s agency at school and in local communities, supported by school staff, community facilitators, cultural mediators and families. CHILD-UP studied the current practices at school and in the local contexts of seven EU countries (Belgium, Finland, Germany, Italy, Poland, Sweden, United Kingdom) with different migrant communities and profiles, aiming to identify, analyse and disseminate evidence of good practices supporting children’s agency and hybrid integration. The project was supported by the involvement of stakeholders at the local and international level, discussing its approach, multiplying good practices and influencing public policies. CHILD-UP offered the school community first the opportunity to be actively involved in the research, then several tools to reflect and act for successful hybrid integration of migrant children. This can improve not only the migrant children condition, but that of all children, families and communities. CHILD-UP offers new evidence through substantial field research, supporting both policy makers and civil society in establishing more effective policies of hybrid integration.