The aim of this study was to determine the effect of student-centered practices in a life science course at the national level. In line with this purpose, searches were conducted in the identified databases. This meta-analysis study employed 39 experimental studies (48 comparison data sets). Upon completing the analysis, it was observed that the studies exhibited heterogeneity. Therefore, a random effects model was employed. Hedge's g effect size was calculated for each dataset, and overall effect levels and significance values were examined. Cohen's (1988) classification was used to interpret the effect size. Data related to the studies included in the meta-analysis were entered into the Comprehensive Meta-Analysis (CMA) software program and analyzed. According to the results of the Funnel plot, Rosenthal Safe N, Duval and Tweedie tests, no publication bias was found in the analyzed studies. Additionally, the type of publication, grade level, week of implementation, and geographical region where the studies took place were analyzed as moderator variables that might affect the effect size. The analysis revealed that student-centered practices in the life science course had a large effect (Hedge's g=0.911). Furthermore, the effect size varied based on publication type, grade level, and geographical region but not on the implementation week. Consequently, student-centered practices and activities are recommended to enhance student achievement in the life science course.