Harahap, Rofiqoh Hasan, et al. “PROBLEM-BASED LEARNING IN PRIMARY SCHOOLS: ENHANCING CONCEPTUAL UNDERSTANDING AND PROBLEM-SOLVING SKILLS”. International Journal of Educatio Elementaria and Psychologia, vol. 3, no. 2, Apr. 2026, pp. 180-98, doi:10.70177/ijeep.v3i2.4225.