<![CDATA[This study was motivated by the low quality of the learning process and outcomes in the IPAS (Natural and Social Sciences) subject among fifth-grade students at SDN 100/II Muara Bungo. The learning process remained largely teacher-centered, resulting in students being passive and disengaged, while cooperation and interaction among students were suboptimal. To address these issues, the Group Investigation learning model was implemented; this model emphasizes cooperation, group inquiry, discussion, and active student participation in knowledge acquisition. The objective of this study was to improve the IPAS learning process and outcomes for fifth-grade students at SDN 100/II Muara Bungo using the Group Investigation model. This study employed Classroom Action Research (CAR) based on the Arikunto model and was conducted over two cycles. Each cycle comprised stages of planning, action implementation, observation, and reflection. The research subjects were fifth-grade students at SDN 100/II Muara Bungo. Data collection techniques included observation and learning outcome tests. The data were analyzed using both qualitative and quantitative methods. The results indicate that the implementation of the Group Investigation model improved the students' IPAS learning process and outcomes. Teacher activity increased from 75% in Cycle I (Meeting I) to 91.66% in Cycle II (Meeting II), while student activity rose from 30% to 90%. Student learning outcomes also improved; the average score increased from 71.25 in Cycle I to 81.75 in Cycle II, and the percentage of classical mastery increased from 45% to 90%. Thus, the Group Investigation learning model proved effective in enhancing the IPAS learning process and outcomes for fifth-grade students at SDN 100/II Muara Bungo, and the study's success indicators were achieved.]]>
