Impact of Ability Grouping on Eighth-Grade Students’ Mathematics Achievement

This study investigated the impacts of ability grouping on eighth-grade students’ mathematics achievement at Phordung Lower Secondary School. A convergent parallel mixed methods design was employed, where quantitative and qualitative data were collected concurrently from 54 eighth-grade students (29 males, 25 females). The quantitative component included a standardised test, and the qualitative component included students’ opinions collected through a focus group discussion and observation notes. Quantitative data were analysed using the Kruskal-Wallis Test, followed by the Tukey Honestly Significant Difference post hoc test, and qualitative data were analysed using an inductive content analysis approach. Although all ability groups showed gains in their test scores, high-ability students outperformed the lower- and mid-ability students. Students’ positive attitudes toward same-ability grouping, as evidenced by their focus group discussions, were linked to gains in test scores compared to their experiences in mixed-ability grouping. While this study found increases in test scores and positive attitudes, ability grouping creates a learning gap between higher and lower ability groups. Therefore, educators should consider the benefits and drawbacks before implementing ability grouping.