Youth development programs increasingly leverage physical activity as an experiential platform for acquiring non-cognitive skills. This paper investigates the impact of a structured sports-based intervention on leadership, teamwork, and social competence among school students. Utilizing a pre-test and post-test experimental design with control and intervention groups, school-aged participants were engaged in a multi-week athletic curriculum emphasizing cooperative gameplay, peer mentorship, and reflective debriefing. Quantitative assessments were conducted using standardized psychosocial evaluation scales to measure changes in perceived leadership capability, collaborative behavior, and social adaptability. The results demonstrate statistically significant improvements in the intervention group across all three domains compared to the control cohort. Specifically, participants exhibited enhanced peer communication, higher conflict-resolution capabilities, increased empathy, and greater willingness to take initiative in group settings. These findings indicate that deliberate, mastery-oriented sports interventions serve as effective pedagogical instruments for developing interpersonal competencies, providing educators and policy makers with an empirical foundation for integrating structured sports programs into school curricula.