“The Influence of The Problem-Based Learning (PBL) Model on The Learning Outcomes of Fourth Grade Students in Social Studies at SD N 040457 Berastagi”. Journal of Pedagogi 1, no. 5 (October 26, 2024): 31–36. Accessed November 30, 2025. https://ejournal-nawalaedu.com/index.php/JOP/article/view/702.