Adolescent problem gambling prevalence rates are reportedly five times higher than in the adult population. Several school-based gambling education programs have been developed in an attempt to reduce problem gambling among adolescents; however few have been empirically evaluated. The aim of this review was to report the outcome of studies empirically evaluating gambling education programs across international jurisdictions. A systematic review following guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement searching five academic databases: PubMed, Scopus, Medline, PsycINFO, and ERIC, was conducted. A total of 20 papers and 19 studies were included after screening and exclusion criteria were applied. All studies reported intervention effects on cognitive outcomes such as knowledge, perceptions, and beliefs. Only nine of the studies attempted to measure intervention effects on behavioural outcomes, and only five of those reported significant changes in gambling behaviour. Of these five, methodological inadequacies were commonly found including brief follow-up periods, lack of control comparison in post hoc analyses, and inconsistencies and misclassifications in the measurement of gambling behaviour, including problem gambling. Based on this review, recommendations are offered for the future development and evaluation of school-based gambling education programs relating to both methodological and content design and delivery considerations.