حامد تقی زاده

Speaking proficiency is a crucial skill for Iranian EFL learners, yet it remains one of the most challenging aspects of language acquisition due to traditional, teacher-centered instruction and a lack of communicative practice. This study examines the effects of Differentiated Instruction (DI) and Gamification (G) on the Complexity, Accuracy, and Fluency (CAF) of Iranian EFL learners’ speaking skills. A quasi-experimental design was employed, involving 108 B2-level learners from Safir Language Institute, Iran. Participants were divided into three groups: one receiving DI-based instruction, another engaging in Gamification-based tasks, and a control group following conventional teaching methods. The study utilized pre- and post-tests of speaking performance, evaluated through CAF metrics, alongside qualitative interviews to explore learners’ perceptions. Statistical analyses revealed significant improvements in all three dimensions of speaking in the experimental groups, with DI showing greater gains in accuracy and complexity, while G was more effective in enhancing fluency. Qualitative findings indicated that both approaches increased learner engagement, motivation, and confidence. These results suggest that DI and Gamification are effective pedagogical strategies for improving speaking proficiency and should be integrated into EFL curricula to optimize learning outcomes.