Colin P. Green, Ole Henning Nyhus and Kari Vea Salvanes examine two forms of testing, complex but low-stakes mathematics tests and relatively easy screening tests aimed at identifying children in need of educational assistance. In general, we demonstrate zero effects of testing exposure on later test score performance but benefits for screening tests on low-performing students. While we demonstrate no negative effects on student welfare, we do find an indication that testing improves aspects of teaching practices and students’ perceptions of teacher feedback and engagement.