Recent theorising of children’s agency has focused on relational approaches. Critical realism can provide additional theoretical reinforcement as it demands a focus on relatively enduring patterns of disadvantage and potential powers. Participatory research with children and young people confirms the relevance of Archer’s conception of influence achieved by Selves, Social Actors, and Primary and Corporate Agents. In moments, children within organised collectivities set agendas and shape some circumstances that affect others. When modified by generation-sensitive insights, Archer’s framework may provide understandings of children’s individual and collective agency. These insights might also strengthen critical realist understandings of children and childhood.