Domain-Specific Mathematics Performance of Grade 8 Students: Evidence from a K to 12 Achievement Test

This study analyzed the domain-specific mathematics performance of Grade 8 students at Southern Baptist College using the results of the Center for Educational Measurement (CEM) K to 12 Mathematics Achievement Test for School Year 2024–2025. It specifically aimed to determine students’ performance in Patterns and Algebra, Geometry, and Statistics and Probability based on scaled scores, describe the distribution of overall performance levels, and examine significant differences among the three mathematics domains. The study employed a descriptive-comparative research design using secondary data from 84 Grade 8 students. Data were analyzed using Jamovi statistical software through descriptive statistics, frequency and percentage distribution, the Shapiro–Wilk test of normality, and the Friedman test for repeated measures. Results showed that Statistics and Probability obtained the highest mean score, followed by Geometry, while Patterns and Algebra obtained the lowest mean score. However, no statistically significant differences were found among the three mathematics domains (χ² = 2.46, p = .292). In terms of overall performance, most students were classified under the Average and Moving Towards Average performance levels, with only a small proportion reaching Excellence. The findings suggest that Grade 8 students demonstrated comparable performance across the three mathematics domains, indicating generally balanced achievement in the assessed competencies. The study concludes that the results provide baseline evidence that may inform instructional planning and the development of targeted mathematics intervention programs. It is recommended that targeted interventions be implemented to strengthen students’ proficiency in Patterns and Algebra and further enhance overall mathematics achievement.