The Effects of Blended Learning in University Science Courses: A Meta-Analytic Review

As digital transformation in education advances, blended learning is evolving from an innovative approach into a mainstream format in higher education, significantly reshaping traditional teaching ecosystems. Current research presents inconsistent findings on how blended learning affects student outcomes in undergraduate science courses. To address this, a meta-analysis was conducted, synthesizing 28 empirical studies from China and abroad. The results indicate that: (1) Blended learning has a moderately positive overall effect on learning outcomes in university science courses; (2) Regarding instructional design, full-semester duration, small teaching scale, and a moderate proportion of online learning show stronger effectiveness; (3) In terms of instructional support, videos and reading materials play the most essential foundational role, while learning management systems prove more effective than online meeting tools; (4) Regarding assessment, formative evaluation and big data-based comprehensive evaluation outperform summative evaluation. Based on these findings, this study proposes building a blended learning system centered on "scientific cognitive principles", aimed at systematically enhancing students’ disciplinary literacy and higher-order thinking skills through optimized course structure, deeper technology integration, and diversified assessment practices.