Effects of online teacher professional development on teacher-, classroom-, and student-level outcomes: A meta-analysis

Teachers' professional development is crucial for effective classroom practice. Due to its advantages, many teachers have participated in online professional development (OPD) in recent years. Numerous studies have investigated the participation and effect of first to 12th grade inservice teachers' OPD participation on the teacher, classroom practice, or student level. However, a comprehensive meta-analysis of these studies is missing. This meta-analysis summarizes findings from 102 quantitative studies with a pre-posttest design. The results indicate medium effects of OPD participation on the teacher level (Hedges' g = 0.71) and on the classroom level (Hedges' g = 0.55) and a small effect on the student level (Hedges' g = 0.19). We included Desimones' (2009) core features of effective PD participation as moderators. We found that the core feature of collective participation positively influenced the effect size of the classroom level. Furthermore, we found that studies that employed a control-group design reported significantly lower effect sizes on teacher-level outcomes than studies that used a within-subject design. On the student's level, studies with asynchronous OPD reported significantly smaller effect sizes than studies with a synchronous OPD format. Our results aim to provide research, policymakers, educational stakeholders, and teachers with the clarity that OPD is effective on several levels and should, therefore, be encouraged.