This Campbell systematic review examines the effects of targeted school-based interventions on standardised tests in reading and maths. The review analyses evidence from 71 studies, 52 of which are randomised controlled trials. School-based interventions targeting students with, or at risk of, academic difficulties in Grades 7-12 have on average positive effects on standardised tests in reading and maths. The most effective interventions have the potential to considerably decrease the gap between at-risk and not-at-risk students. Effects vary substantially between interventions, however, and the evidence for using certain instructional methods or targeting certain domains is weaker. This review examines the effects of a broad range of school-based interventions targeting students with, or at risk of, academic difficulties on standardised tests in reading and maths. Included interventions changed instructional methods by, for example, using peer-assisted learning, introducing financial incentives, giving instruction in small groups, providing more progress monitoring, using computer-assisted instruction, and giving teachers access to subject-specific coaching. [This summary is based on Dietrichson, J, Filges, T, Klokker, RH, Viinholt, BCA, Bøg, M, Jensen, UH. Targeted school-based interventions for improving reading and mathematics for students with, or at risk of, academic difficulties in Grades 7-12: A systematic review. "Campbell Systematic Reviews." 2020; 16:e1081. https://bibliotheek.ehb.be:2102/10.1002/cl2.1081.]