Almost every educational system in the world regards numeracy and literacy as more important than the arts. In the UK arts interest groups and politicians have, for years, asked for arts education to be accorded the same priority arguing that arts contribute to learning and development of useful skills. It is not clear if these claims were based on evidence. The aim of this review is to examine international empirical evidence to establish whether arts participation could lead to improvements in children's learning and other wider outcomes, and to identify arts activities with the best evidence of success. A search of 11 databases identified 76,195 reports, of which 200 were included for analysis. No studies with high levels of supporting evidence were found because of serious weaknesses in design. Tentative evidence suggests that music training and integrating drama in the classroom may have beneficial effects. This finding has to be taken with caution because of weaknesses in these studies, the lack of replication and inconsistent findings across studies. More robust and rigorous evaluations are needed to test the causal links. However, if improving attainment is the aim then arts may not be the solution. Promising programmes already exist that can boost learning. Given the lack of evidence so far, perhaps we should think more broadly about the purpose of arts.