Meylan Hanna Sitinjak; Theresia Siahaan; Hetdy Sitio. The Influence of The Student Teams Achievement Divisions (STAD) Cooperative Learning Model on Class III Student Learning Outcomes Theme 1 Subtheme 1 at UPTD SD Negeri 125543 Pematang Siantar. IJIST 2023, 1, 401-408.