This longitudinal study addresses a critical gap in understanding the divergent evolution of sub-national education systems within a single national framework. It investigates the comparative development of primary education across Zambia’s provinces from 2021 to 2025, analysing disparities in resource allocation, pedagogical quality, and learner outcomes. The research employs a sequential mixed-methods design. Quantitative analysis utilises verified annual panel data (2021-2023) from government and institutional reports, with projected 2024-2025 data clearly modelled from established trends to address temporal scope. This is integrated with biennial qualitative fieldwork (2022, 2024) involving semi-structured interviews and classroom observations in purposively sampled rural and urban districts, with thematic analysis applied. Findings reveal a widening equity gap: provinces with greater initial infrastructure and teaching capital demonstrate accelerated improvements in pupil literacy and numeracy. Conversely, more remote regions exhibit stagnation, exacerbated by inconsistent textbook delivery and teacher attrition. The study contends that nationally aggregated data often masks these entrenched regional inequalities, which undermine goals of inclusive quality education. It concludes that equitable development in Zambia necessitates a shift from uniform policies towards context-sensitive, regionally differentiated interventions, underscoring the imperative for educational planning to account for intra-country heterogeneity.