This study examines the role of game-based learning (GBL) in supporting vocabulary retention among Vietnamese Grade 8 EFL students. The study was conducted within authentic lower secondary classroom settings where games were regularly integrated into vocabulary instruction. A mixed-methods design was employed to investigate both students’ vocabulary performance and teachers’ perceptions of game-based instruction. Quantitative data were collected through a vocabulary retention test administered to 100 Grade 8 students, assessing recognition, recall, and productive vocabulary use. In addition, semi-structured interviews with three English teachers explored perceptions of the effectiveness and challenges of implementing GBL in vocabulary teaching. The findings indicated relatively positive performance across all three dimensions of vocabulary retention, with recognition showing the strongest results and productive vocabulary use demonstrating substantial learner achievement. The results suggest that retrieval-oriented and communicative game activities may contribute to vocabulary retention through repeated exposure, active retrieval, and contextualized language use. The qualitative findings further indicated that teachers viewed GBL as an engaging and pedagogically valuable approach that increased student participation, interaction, and classroom engagement. Nevertheless, several implementation challenges were identified, including classroom management difficulties, time constraints, and technological limitations. Overall, the study highlights the pedagogical potential of game-based learning in promoting deeper vocabulary retention in Vietnamese lower secondary EFL classrooms. The findings also suggest that different game formats may support different dimensions of vocabulary learning unevenly, particularly receptive and productive vocabulary development.
Duong et al. (Thu,) studied this question.