Abstract
Inclusive education requires teachers to possess adaptive pedagogical competencies. Based on in-depth observations and interviews, many teachers in high school/equivalent private level in Sleman Regency still face challenges in developing pedagogical competence, particularly in adapting learning strategies to students’ diverse needs and preparing responsive teaching materials. This study aims to measure and analyze the partial and simultaneous effects of principals’ leadership and organizational culture on teachers’ pedagogical competence in private inclusive schools at the high school/equivalent private level in Sleman Regency. This study employed a quantitative method using a survey and explanatory approach, with a descriptive non-experimental correlational design and a causal-associative approach. The research was conducted in four private inclusive schools: SMA Gama Yogyakarta, SMK Bina Harapan, SMK Muhammadiyah 1 Tempel, and SMKS Budi Mulia Dua. The population consisted of 54 teachers, all of whom were included as the research sample based on Gay et al. (2019), who states that when the number of research subjects is fewer than 100, the entire population may be used as the sample. Data were collected using a closed questionnaire comprising 52 statements covering principals’ leadership (14 items), organizational culture (22 items), and teachers’ pedagogical competence (16 items). Data were analyzed using prerequisite tests, and simple and multiple linear regression with the assistance of SPSS version 26. The results showed that: (1) principals’ leadership had a positive and significant effect on teachers’ pedagogical competence (Sig. 0.000 < 0.05); (2) organizational culture had a positive and significant effect (Sig. 0.000 < 0.05); and (3) principals’ leadership and organizational culture simultaneously had a positive and significant effect on teachers’ pedagogical competence (Sig. 0.000 < 0.05). The coefficient of determination (R²) was 0.500, indicating that the two independent variables jointly explained 50% of the variation in teachers’ pedagogical competence.