This mixed-methods study examined the implementation challenges of Uganda's Competency-Based Curriculum (CBC) as productive struggles that could catalyze educational transformation. Employing a convergent parallel design, the research was conducted across 45 purposively selected primary schools in five districts representing diverse geographical regions, with a sample of 450 participants comprising 270 teachers, 45 head teachers, 90 education officials, and 45 Parent-Teacher Association representatives, providing 80% statistical power to detect medium effect sizes. Quantitative data were collected using validated questionnaires measuring implementation challenges, adaptive strategies, teacher competence, and implementation effectiveness, while qualitative data were gathered through focus group discussions, semi-structured interviews, classroom observations, and document analysis. Statistical analyses included descriptive statistics, ANOVA, multiple linear regression, and structural equation modeling, complemented by thematic analysis of qualitative data. Results revealed that insufficient instructional materials (M = 4.47, SD = 0.65), inadequate infrastructure (M = 4.29, SD = 0.77), large class sizes (M = 4.38, SD = 0.71), and inadequate teacher training (M = 4.23, SD = 0.78) constituted the most severe implementation challenges, with rural schools experiencing significantly more acute difficulties than urban schools across all domains (F = 29.87, p < 0.001, η² = 0.223). Structural equation modeling validated all three hypotheses with excellent model fit (CFI = 0.953, RMSEA = 0.055): teacher training significantly influenced pedagogical quality both directly (β = 0.189, p < 0.001) and through teacher competence (indirect effect β = 0.445, p < 0.001); schools employing more adaptive strategies demonstrated significantly better implementation quality and learning outcomes (total effect β = 0.387, p < 0.001); and stakeholder feedback mechanisms significantly improved professional development quality, which enhanced both teacher confidence (β = 0.671, p < 0.001) and implementation effectiveness (β = 0.594, p < 0.001). Qualitative findings revealed that teachers developed innovative adaptations including material improvisation, peer collaboration networks, modified assessment approaches, and flexible grouping strategies that made competency-based learning feasible within resource-constrained environments. The study concluded that CBC implementation challenges, while substantial, represented productive struggles that generated valuable innovations and insights when met with adequate support, collaborative problem-solving, and continuous improvement systems. However, transformation of struggles from destructive to productive required systematic investment in teacher capacity building, equitable resource allocation, sustained professional development, and institutionalized mechanisms for incorporating stakeholder feedback into reform processes. The research contributed empirical evidence supporting a paradigm shift from viewing implementation challenges as reform failures toward recognizing them as collective learning opportunities that, when properly leveraged, could catalyze genuine educational transformation in Uganda and similar developing contexts undertaking competency-based curriculum reforms.