Abstract. Achievement tests are essential in assessing educational outcomes and student performance in various subjects. Previous literature has revealed that demographic and administrative factors often affect their results. This study aims to determine the influence of socio-demographic characteristics, teaching effectiveness, and management practices on National Achievement Test (NAT) outcomes among Grade 10 students in the Schools Division of Isabela to provide a basis for an enhancement program. Quantitative research under descriptive-correlational research design was used to collect data from 12 schools and analyze their performance in English, Filipino, Mathematics, and Araling Panlipunan. Results revealed that disparities in performance across subjects, with students struggling the most in Mathematics (M=37.74, low proficient) and critical thinking components. Additionally, socio-demographic factors such as parental education (τb = 0.099, p = .015), economic status (τb = 0.127, p=.001), and school size (τb = -0.126, p =.002) significantly impacted test outcomes, highlighting the need for targeted support. Teaching effectiveness, specifically preparation for instruction and management practices, was also a vital determinant of performance. These findings highlighted the necessity of systemic reforms that center on equitable resource allocation, consistent professional development, and leadership development in schools. This paper suggests that to improve the NAT performance, there is a need for a change of paradigm in the curricula towards a more responsive and evidence-based policy making.

Keywords: Education reform; Management practices; National Achievement Test; Socio-demographic factors; Teaching effectiveness.