This study aims to improve the learning outcomes of class III students at SDN Grabahan through the application of the STAD type cooperative learning model in thematic learning. This study uses a class action research method with two cycles. The research participants were 16 grade III students at SDN Grabahan. Data was collected through interviews, observation, test results, and documentation. The results of the study showed that in cycle 1 there was 1 student who had not achieved the value completeness, but in cycle 2 all 16 students succeeded in achieving the value completeness. The majority of students' responses to the STAD cooperative learning strategy were positive, in which students responded usefully and enjoyed learning. This study indicates that the application of the STAD type cooperative learning model effectively improves student learning outcomes and creates an active, inclusive, and supportive learning environment. This research makes a positive contribution in efforts to improve the quality of learning and can be a reference for developing more effective learning strategies in the future. Keywords: Cooperative Learning Model, STAD, Learning Outcomes, Thematic Learning