Empirical Analysis of the Relationship Between Curriculum Alignment and Student Achievement in Senior Secondary Mathematics Across the Six Geopolitical Zones

Curriculum alignment, the degree of coherence between intended curriculum, taught curriculum, and assessed curriculum, is theorised as a key determinant of student achievement, and its empirical characterisation across Nigeria's diverse educational contexts fills an important evidence gap in national curriculum policy. This study empirically analysed the relationship between curriculum alignment levels and WAEC Mathematics achievement across six states representing each geopolitical zone: Sokoto (NW), Gombe (NE), Abuja FCT (NC), Delta (SS), Anambra (SE), and Ogun (SW). A multi-state survey design was employed, with 180 SS3 Mathematics teachers (30 per state) completing a Curriculum Alignment Inventory assessing objective coverage, instructional fidelity, and assessment alignment. Teachers' students' 2023 WAEC Mathematics results (n = 3,240) were linked to teacher alignment scores. Multiple regression analysis showed that curriculum alignment scores were significant positive predictors of WAEC pass rates (beta = 0.52, p < 0.001) after controlling for school type, state, and teacher qualification. The alignment-achievement relationship was strongest in Ogun and Anambra States and weakest in Gombe and Sokoto States. Schools with high alignment scores had WAEC pass rates averaging 22.4 percentage points higher than low-alignment schools. The study fills an empirical gap in national-level curriculum alignment research and recommends a national Curriculum Alignment Monitoring Initiative, subject-specific alignment guides for all WAEC examination subjects, and alignment-focused teacher professional development as the highest-priority interventions. Keywords: curriculum alignment, student achievement, WAEC Mathematics, multi-state study, curriculum coherence