Coaching Principals for Inclusive School Improvement: Development and Empirical Validation of a Special Education Leadership Training Model

Abstract

This study aimed to develop and validate a Transformative Leadership Coaching (TLC)-based training model to improve the leadership quality of public junior high school principals in Gunungsitoli City, Indonesia.The study employed a research and development design adapted from the Plomp model, covering preliminary investigation, design, realization, evaluation, revision, and implementation. All 26 public junior high school principals participated through total sampling. Data were collected using expert validation sheets, implementation checklists, pretest-posttest instruments, questionnaires, observations, and semi-structured interviews. Quantitative data were analyzed using percentage-based validity criteria, intraclass correlation coefficient, chi-square normality testing, and normalized gain analysis, while qualitative data were analyzed thematically. The TLC model met the criteria of validity, practicality, and effectiveness. Expert review confirmed strong content and construct validity, while implementation results showed high feasibility and positive participant responses. Pretest-posttest results indicated meaningful improvement in leadership competence, supported by moderate-to-high normalized gain scores. Observational and interview data further showed improvements in reflective capacity, strategic thinking, instructional leadership, and collaborative engagement. The TLC model offers a theoretically grounded and context-responsive framework for principal professional development. By integrating transformative learning and structured coaching cycles, the model provides a practical pathway for strengthening school leadership in decentralized and resource-constrained educational settings.