This study reconceptualizes lesson management as a vision-driven, adaptive design process. It investigates how integrating social design-based experimentation (SDBE) with lesson study – framed as a design ecology – can illuminate teachers' capacities for sustainable, equity-oriented instructional improvement.
A year-long qualitative case study was conducted with a Japanese elementary school teacher engaged in lesson study. Data included classroom observations, reflective memos, teaching records and instructional artefacts. Analysis drew on three SDBE lenses: recognising generative tensions, redesigning participation structures and stabilising new classroom norms within the evolving design ecology.
Instructional gaps – interpreted through the teacher's evolving vision – served as catalysts for pedagogical innovation. The teacher gradually shifted from behaviour control to fostering dialogic engagement and student autonomy. Classroom norms developed through iterative cycles of redesign and stabilisation, shaped by both formal lesson study events and informal collegial interactions.
Though limited to a single case, the study offers a transferable framework for understanding lesson management as an iterative design process. Future research could examine this model's applicability across diverse educational settings.
Teacher education programmes can adopt SDBE principles to help cultivate adaptive expertise. Viewing lesson study as a design ecology can support participatory and inclusive classroom environments through structured, sustained reflection.
The paper's value lies in its integration of SDBE and lesson study. By reframing lesson study as a design ecology, it presents a dynamic framework for analysing how teachers' professional growth is nurtured through the interplay of personal vision, collaborative inquiry and responsive practice.
