Background: Uganda's youth face mounting pressures from examination-focused education systems and societal expectations that prioritize traditional career paths while undervaluing entrepreneurship, resulting in graduates who lack purpose, practical skills, and confidence to pursue meaningful ventures despite a critical need for job creation through enterprise development. Objective: This study developed and evaluated a dual-curriculum model integrating purpose discovery and entrepreneurship education with conventional academic learning to nurture purposeful entrepreneurs among Ugandan teenagers. Methods: A mixed-methods quasi-experimental design was employed across six secondary schools in central Uganda from January to December 2024, involving 480 students aged 14-17 years (240 intervention, 240 control) selected through stratified random sampling. The 12-month intervention consisted of weekly purpose-discovery workshops utilizing the Stanford Purpose Project framework, bi-weekly entrepreneurship training modules covering opportunity identification, business planning, and financial literacy, and mentorship sessions with local entrepreneurs, all integrated alongside regular academic coursework. Data were collected through pre-test and post-test assessments, structured questionnaires, interviews, focus groups, and academic records. Quantitative analysis included univariate descriptive statistics, bivariate analyses using independent t-tests and chi-square tests, Pearson correlations examining relationships among variables, and multivariable regression models identifying predictors of entrepreneurial intentions while controlling for demographic, socioeconomic, and academic confounders, with difference-in-differences analysis estimating causal intervention effects. Results: Baseline characteristics were well-balanced between groups (all p>0.05), with participants demonstrating low initial purpose scores (mean≈42/100), low entrepreneurial self-efficacy (mean≈38/100), and high perceived academic pressure (mean≈77/100). Post-intervention bivariate analyses revealed statistically significant differences favoring the intervention group across all primary outcomes: purpose score (mean difference=26.2 points, p