School sports, if not designed within a coherent and sustainable legal framework, may fail to ensure student safety and instead contribute to institutional instability, increased litigation, and reduced educational equity. This study aimed to develop "A Model for the Sustainabilization of Sports Rights in the Developmental System of Iranian Schools" to identify key dimensions affecting the durability and effectiveness of the school sports legal system and to facilitate sustainable development in education. The research approach was grounded theory, following the systematic narrative of Strauss and Corbin. The statistical population consisted of all experts and specialists in the fields of sports law, sports management, and education. Using purposive sampling and the snowball technique, with theoretical saturation as the criterion, 13 individuals were selected as the final sample. The data collection tool was semi-structured interviews. After recording and transcription, the data underwent a three-stage analysis of open, axial, and selective coding. During open coding, 107 initial concepts were extracted from the data. The software used to manage and facilitate the coding process was MAXQDA (Version 2020). The qualitative data analysis led to the identification of six main categories: Education and Empowerment, Policy-making and Responsibility, Governance System and Operational Efficiency, Core Infrastructure and Technology, Factors of Good Governance, and the Core of Cultural and Social Synergy. The findings indicate that the institutionalization of sports law in schools is a dynamic and multidimensional process, requiring simultaneous attention to structural, cultural, and educational dimensions. Ultimately, it can be concluded that although macro-level challenges such as lack of training, weak laws, and inadequate infrastructure seem common across all sports contexts, the operational strategies and action priorities for institutionalization are heavily influenced by the specific context (e.g., schools versus professional clubs). Success hinges on understanding these nuances and employing a multidimensional and coordinated approach.