The Effect of Problem-Based Learning on Students’ Environmental Literacy: A Meta-Analysis

Abstract

Environmental literacy is essential for enabling students to understand environmental problems and make responsible decisions. This study aimed to estimate the overall effect of Problem-Based Learning (PBL) on students’ environmental literacy knowledge and to examine variation across included studies. A systematic review and meta-analysis were conducted using eight experimental and quasi-experimental studies published between 2018 and 2025. Studies were identified through Google Scholar using Publish or Perish and selected according to criteria requiring experimental and control groups, post-test means, standard deviations, and sample sizes. Effect sizes were calculated using Hedges’ g under a random-effects model. Heterogeneity was examined using Cochran’s Q, tau-squared, and I-squared statistics, while potential publication bias was assessed through funnel-plot inspection. The pooled effect size was large and statistically significant (Hedges’ g = 0.86, 95% CI [0.37, 1.36], p = .005), indicating that PBL improved students’ environmental literacy knowledge compared with non-PBL instruction. Significant heterogeneity was identified, Q(7) = 30.74, p < .001, I² = 77.46%, showing considerable variation across studies. These findings support the integration of authentic environmental problems into classroom learning. However, differences in educational levels, instruments, and implementation procedures should be considered when applying PBL across contexts. The funnel plot showed no pronounced asymmetry.