This study examined the effects of two modes of homework on secondary school Social Studies students’ academic achievement in Oyo Metropolis, Nigeria. The study adopted a quasi-experimental design involving pretest posttest control groups. The sample consisted of 300 Junior Secondary School two (JSS 2) students selected through simple random sampling techniques and assigned into three groups: traditional (100), online homework (100), and control group (100). Two instruments were used for data collection: Social Studies Achievement Test (SSAT) and Students' Focus Group Discussion Guide (SFGDG). Quantitative data was analyzed using the descriptive statistics such as mean and standard deviation. Inferential statistics Analysis of Covariance (ANCOVA) was used to test the hypotheses at 0.05 level of significance while the qualitative data were analyzed using content analysis. Findings revealed that both traditional and online homework modes significantly improved students' academic achievement in Social Studies compared to the control group. There was a significant main effect of treatment on students’ academic achievement in Social Studies. Gender and age moderated academic achievement. The study concludes that the purposeful integration of traditional and online homework into the Social Studies instruction holds considerable promise for improving academic achievement among Junior Secondary School students in Nigeria. It is recommended that Social Studies teachers should deliberately incorporate both traditional and online homework strategies into their instruction to foster students' academic achievement.