<![CDATA[This study evaluates the effectiveness of a Virtual Reality (VR)–based adaptive learning application in enhancing high school students’ understanding of chemical compounds. The primary objective was to quantitatively assess the impact of the VR intervention on student learning outcomes across two distinct cohorts (N = 78). A pretest–posttest control-group design was employed, with two parallel groups (Group A and Group B) to ensure internal validity and comparability of results. The findings consistently indicate a marked contrast between the experimental and control conditions. Students in the control groups showed declines in performance, with negative learning gains of −8.32 and −15.20, suggesting learning loss when conventional instructional methods were used. In contrast, students exposed to the VR-based adaptive learning application demonstrated positive learning gains of +2.90 and +9.70, reflecting meaningful improvements in conceptual understanding. Further analysis of the intervention’s impact revealed effect sizes ranging from medium (Cohen’s d = 0.722) to very large (d = 2.182). These results indicate not only statistical significance but also substantial practical significance. Overall, the findings provide strong empirical evidence that the VR-based adaptive learning application is effective in preventing learning loss and significantly enhancing students’ understanding of chemical compounds when compared to traditional instructional approaches.]]>
