Chaiyaphornkaew, K., Chaowarakul, J., Sintanapanya, A. and Viphoouparakhot, B. 2026. A development model of effective educational administration in the 21st-century schools under the Salesian Foundation of Thailand . APHEIT International Journal of Interdisciplinary Social Sciences and Technology. 15, 1 (Jun. 2026), 22–34.