Abstract
This study examined the misalignment between cognitive development and mathematics education in senior secondary schools. Using an ex post facto research design and a descriptive survey approach, data were collected from the Senior Secondary Mathematics Achievement Test (SSMAT), which showed a strong reliability coefficient (r = 0.89). The analysis, which included descriptive statistics and independent sample t-tests, revealed that gender does not have a significant impact on student's performance in SSS2 mathematics across different content areas (number and numeration, algebra, geometry, and everyday statistics) and cognitive dimensions (recall, conceptual understanding, and reasoning). The results highlight the need for a comprehensive approach to mathematics education that balances content coverage and the development of cognitive skills. Addressing this misalignment can improve students' ability to creatively apply mathematical concepts, think critically, and effectively communicate their mathematical ideas, ultimately enhancing overall academic achievement. Our study identifies clear gaps in current educational assessment methods, emphasizing the importance of focusing on content and cognitive dimensions. The results will assist in developing targeted instructional strategies that align with cognitive demands, improve teaching effectiveness, and inform educational policy to enhance student outcomes in mathematics.