This study aimed to explain the roles of teachers, principals, and parents in enhancing meaningful learning in multi-level classrooms and to develop a context-based conceptual model using a qualitative grounded theory approach. Purposive sampling followed by theoretical sampling was employed. Data were collected through 27 semi-structured interviews with 12 teachers, 8 principals, and 7 parents in multi-level schools in Mazandaran Province, Iran, and analyzed using Strauss and Corbin’s three-stage coding process. The findings revealed that meaningful learning in multi-level classrooms emerges from the dynamic interaction of these three key actors and is achieved when teachers’ instructional strategies, principals’ supportive leadership, and parents’ informed participation are aligned in a synergistic manner. Causal conditions such as heterogeneous learning levels, contextual conditions including limited resources, and intervening conditions such as parental attitudes and principals’ leadership styles were found to influence the implementation of instructional strategies. The final conceptual model indicates that meaningful learning is not the result of isolated individual efforts but develops through a network of coordinated actions. Moreover, when effectively managed, multi-level classrooms can provide a suitable context for the development of students’ cognitive skills and the enhancement of academic self-efficacy.