Participatory action research and participatory evaluation are two approaches used to involve people in public affairs, fostering the shared construction of knowledge. Recent decades have seen an increase in the involvement of agents in public activity, a trend that is also evident among young people. Experiences based on youth participatory action research and participatory youth evaluation are discussed in the literature. The main aim of this article is to define these two methodological approaches, and discuss: the role played by agents, the functions implemented, and the main stages. To this end, we have used a systematic documentary analysis of databases and specialist journals between 2010-2021. The results produce a map of internationally published articles regarding participatory action research and participatory youth evaluation. Secondly, a check-list is provided of the two methodological approaches to youth participation; this compiles the functions of the agents involved and the stages involved in both approaches. The article aims to be of use to public administrations and social entities with decision-making powers over actions that favour the involvement of young people in public affairs.