Volume 2 - Issue 3, May - June 2026

The persistent decline in students’ performance in Mathematics has continued to raise concerns among educators and stakeholders, particularly at the secondary school level where achievement in the subject influences future academic and career opportunities. This study examined the effect of differentiated instruction on the academicachievement of senior secondary school students in Mathematics in Ikere Local Government Area of Ekiti State. The study also investigated whether gender influenced students’ achievement when exposed to differentiated instructional strategies. A pretest-posttest quasi-experimental design with a 2 × 2 factorial structure was adopted. The population comprised Senior Secondary School II students in public secondary schools within the study area. Ninety students selected from two schools participated in the study. One school served as the experimental group and was taught using differentiated instruction, while the other served as the control group and received conventional instruction. Data were collected using a researcher-developed Mathematics Achievement Test (MAT) with a reliability coefficient of 0.78. Mean and standard deviation were used to answer the research questions, while independent samples t-test and Analysis of Covariance (ANCOVA) were employed to test the hypotheses atthe 0.05 level of significance. The findings revealed that students exposed to differentiated instruction achieved substantially higher posttest scores (Mean = 59.11) than those taught through conventional methods (Mean = 36.54). The results further showed a significant effect of differentiated instruction on students’ academic achievement in Mathematics after controlling for pretest scores (F(1,79) = 74.460, p < .05). However, no significant difference was found between the achievement of male and female students taught using differentiated instruction. The study concludes that differentiated instruction is an effective approach for improving students’ achievement in Mathematics and can support meaningful learning across diverse groups of learners. It is therefore recommended that Mathematics teachers adopt differentiated instructional practices and that teacher education programmes incorporate training on the effective implementation of differentiated instruction.

Olagoke Michael,"The Effect of Diffentiated Instruction on Academic Achievement of Senior Secondary Schools Students in Mathematics in Ikere LGA in Ekiti State" International Journal of Advanced Multidisciplinary Research and Educational Development, V2(3): Page(843-854) May-June 2026. ISSN: 3107-6513. www.ijamred.com. Published by Scientific and Academic Research Publishing.