Where Do the Didactic Efforts of Teachers Lead? When Grouping Replaces Differentiation

Knowledge about ability grouping exceeds knowledge of specific teaching practices within such groups. This study examines instructional practices in Czech primary schools that employ a hybrid model, combining heterogeneous classroom instruction with ability-based grouping in selected subjects. Drawing on ethnographic observations ( n = 150) and interviews with administrators ( n = 5), teachers ( n = 10), and students ( n = 20), the study reveals a critical paradox: while hybrid grouping aims to facilitate differentiation, it reinforces pedagogical rigidity and fixed mindsets. Teachers differentiate primarily within ability groups, adapting to perceived group-level needs rather than individual progress, while heterogeneous instruction remains predominantly frontal. Ability grouping creates an “illusion of homogeneity,” obscuring within-group variation—a mechanism termed “pedagogical path dependency.” Students from both high- and low-ability groups prefer grouped instruction, perceiving it as more responsive, yet this contradicts inclusive education goals. The study introduces the concept of “organizational pedagogy,” demonstrating how grouping structures actively institutionalize teacher beliefs, with implications for detracking policy and teacher professional development.