Geetanjali Basarkod, Liana S Cahill, Adam Burston, David Barnett, John Mahoney, Shantell Griffith, Ghassani Swaryandini, Emma L Bradshaw, Emma K Devine, Md Akhtaruzzaman, Theresa Dicke, Matti Wilks, Peter Slattery, Alexander K Saeri, Emily A C Grundy, Chris Lonsdale, Herbert W Marsh, Suzanne K Chambers, Michael Noetel
Addressing society's greatest challenges, such as climate change, requires us to act as moral agents. If effective, interventions within schools and universities could cultivate ethical and moral attributes in millions of people. This systematic review and meta-analysis, preregistered on the Open Science Framework ( https://osf.io/bdn2u ), synthesizes evidence from 92 randomized controlled trials conducted in naturalistic education settings across primary, secondary and tertiary education levels (keffects = 381; 12,693 students). Studies were identified through MEDLINE, ProQuest, PsycINFO, PubMed, Scopus and Web of Science databases, last searched on 28 February 2025. Eligible interventions explicitly focused on other-focused moral or ethics education and reported on ethical or moral outcomes. We conducted a three-level multilevel random effects meta-analysis and assessed study quality using the Cochrane Risk of Bias (ROB2) tool. Interventions effectively improved students' moral outcomes compared with control groups (g = 0.65, 95% CI [0.49, 0.81], p < 0.001; nstudies = 54; keffects = 185). While effectiveness did not differ significantly across outcome types, improvements were found for sensitivity, judgement and motivation, with inconclusive evidence for character. Interventions with added student discussions were more effective than those relying solely on unidirectional or passive information transfer. Evidence from studies comparing two alternative ethics interventions (nstudies = 60; keffects = 196) supported the advantages of interactive approaches. While the overall quality of the evidence base was limited, with only one study rated as having low risk of bias and very few having preregistered trials, our review suggests that educational interventions can improve students' ethical and moral attributes, and offers guidance for prioritizing and planning future interventions to increase these attributes at scale.