Differentiation or Ability Grouping? The Practice of Differentiated Instruction in Islamic Education and Student Engagement in High School

Abstract

Differentiated instruction is widely promoted in Indonesia under Kurikulum Merdeka, yet studies rarely examine whether what schools practise under that name actually meets its defining conditions. This case study describes how Islamic Religious Education teachers at a state senior high school implement differentiated instruction and examines the learning engagement that accompanies it. Data were collected through semi-structured interviews with religious education teachers, students, and the vice principal for curriculum, together with classroom observation and document analysis, and were analysed using the interactive model. The study finds that teachers conduct an initial assessment, sort students into low, medium, and high ability groups, and assign tasks of graded complexity, from simple summaries to analysis and digitally sourced presentations. These groups, however, remain fixed rather than flexible, and differentiation rests on academic readiness alone, leaving interest and learning profile unused. Observation shows that high- and medium-ability groups participate actively while the low-ability group remains comparatively passive. Read against Tomlinson's framework, the practice is closer to within-class ability grouping than to differentiation, since flexible regrouping is its defining condition. The study therefore argues that the quality of differentiation should be judged by the mobility it affords students rather than by the variety of tasks it distributes.