This article presents a meta-analysis of the existing literature using Stata 18.0, focusing on the effects of ITSs on learning attitudes, knowledge acquisition, learner motivation, performance, problem-solving skills, test scores, and educational outcomes across different countries and educational levels (k = 30, g = 0.86). The findings suggest that while ITSs can significantly improve learning attitudes and test scores, their effects on knowledge acquisition, learner motivation, performance, and problem-solving skills are less conclusive. The impact of ITSs on educational outcomes also varies across different countries and educational levels, with no significant relationship observed between educational levels and ITS effectiveness. The use of specific ITS designs, such as game-integrated ITSs and ITSs with worked examples, appears to have a more positive impact on educational outcomes. Future research should consider the differential effects of ITS designs and explore ways to enhance their impact on diverse learners and educational contexts.