The study investigated the relationship between participation in extra-curricular activities and students’ academic engagement at Kagezi Primary School in Kisoro District. The objectives of the study were to determine the level of participation in extra-curricular activities, establish the level of students’ academic engagement, and analyze the relationship between participation in extra-curricular activities and students’ academic engagement. The study adopted a correlational research design using both quantitative and qualitative approaches. Data were collected from pupils, teachers, and school administrators using questionnaires and interviews. Multiple linear regression analysis was employed to determine the predictive power of extra-curricular participation on academic engagement. The results revealed that the level of participation in extra-curricular activities at Kagezi Primary School was moderately high, largely influenced by the availability of sports facilities, teacher encouragement, peer influence, and parental support, which collectively explained 57.6% of the variation in students’ participation levels. Similarly, the level of academic engagement among pupils was found to be significantly influenced by teacher feedback, classroom environment, motivation, and parental involvement, accounting for 61% of the variation in engagement. The study further established that participation in extra-curricular activities had a strong and positive relationship with students’ academic engagement, explaining 63% of the variation in academic engagement levels. This implies that pupils who actively participated in sports, music, debates, and leadership activities were more attentive, disciplined, and motivated in their academic work compared to their less-involved peers. The study concluded that extra-curricular activities play a critical role in enhancing academic engagement among primary school learners. Participation in non-academic programs was found to foster teamwork, discipline, self-confidence, and leadership qualities that significantly contribute to improved academic performance. Furthermore, the study concluded that teacher involvement, parental support, and a conducive learning environment are essential in sustaining both co-curricular and academic engagement. It was recommended that the school administration, in collaboration with the Kisoro District Education Department, should invest in adequate sports and cultural facilities and ensure regular maintenance of play areas and equipment. Teachers should be empowered through training and motivation to guide students in both academic and co-curricular programs. Parents and the community should be sensitized on the importance of holistic education and encouraged to participate in school activities. Additionally, extra-curricular activities should be integrated into the school curriculum to ensure sustainability and equitable participation. The Ministry of Education and Sports should also develop policy frameworks and monitoring systems to promote and evaluate co-curricular engagement as part of national education quality standards.