Peer assessment is where students assess the quality of a peer's work. Studies have demonstrated its positive impact on learning yet most of these are in higher education. This study used training to improve the quality of written feedback in a year six primary school classroom. Action Research was selected as a research strategy given the need to find a solution to a classroom problem. Convenience sampling was used as the research focused on the class of children where the issue lay. Methods used to evaluate the quality of training included documents, observations, informal interviews and mind maps. Thematic analysis was used to analyse the data produced. The findings indicate that training may help to improve the quality of children's written feedback in primary school, as it has done in other contexts. Further research is needed to verify these results given the small sample size and absence of controls.