SINTYA KINANTI PUTRI; AMAN SIMARE-MARE. THE ROLE OF PRINCIPAL LEADERSHIP IN IMPROVING LEARNING EFFECTIVENESS IN KINDERGARTEN IN TANJUNG MORAWA DISTRICT. International Journal of Social Science, Educational, Economics, Agriculture Research and Technology (IJSET), [S. l.], v. 5, n. 9, p. 5809–5836, 2026. Disponível em: https://ijset.org/index.php/ijset/article/view/2183. Acesso em: 11 aug. 2026.