IMPLEMENTING DIFFERENTIATED INSTRUCTION STRATEGIES IN MIXED-ABILITY EFL CLASSROOMS: INVESTIGATING TEACHER PERSPECTIVES, CLASSROOM DYNAMICS, AND STUDENT ENGAGEMENT LEVELS

Mixed-ability classrooms have become the structural norm in English as a Foreign Language (EFL) education globally. This shift renders the traditional "one-size-fits-all" pedagogical approach obsolete, as it fails to address the wide variations in student language proficiency, cognitive development, and individual learning profiles. Differentiated Instruction (DI) serves as an alternative framework that allows educators to adapt content, learning processes, and final products to meet diverse student needs. This study investigates teacher perspectives, classroom dynamics, and student engagement levels within mixed-ability secondary EFL classrooms following the strategic implementation of DI. Employing a mixed-methods research design, quantitative data were gathered through structured student engagement surveys ($N=120$), while qualitative insights were extracted via semi-structured interviews with secondary school EFL teachers ($N=8$). The quantitative findings revealed a statistically significant increase in behavioral, emotional, and cognitive student engagement levels after DI strategies were introduced. Qualitative analysis further demonstrated that while teachers maintain highly positive attitudes toward the inclusive nature of DI, its practical application is hindered by structural constraints, including large class sizes, limited preparation time, and a lack of formal training. Additionally, classroom dynamics shifted from traditional teacher-led instruction to cooperative learning environments characterized by flexible grouping and reduced learner anxiety. The study concludes with institutional recommendations for teacher professional development to bridge the gap between theoretical DI models and everyday classroom practice.