This study investigated the effectiveness of computer-supported jigsaw II cooperative learning strategies on the performance of senior secondary students in physics. The study also determined how moderating variables of gender and attitude to physics when Jigsaw II cooperative learning is used as an instructional strategy. Purposive sampling technique was used to select two senior secondary school class II physics students from four intact classes in Minna, Niger State, Nigeria. 80 students from two intact classes were assigned into Jigsaw II and Individualized Computer Instruction (ICI) groups. Computer-Assisted Learning Package (CALP) on physics and Physics Achievement Test (PAT) were used as treatment and test instruments. Analysis of Covariance and Scheffe’s test were used for data analysis. Findings indicated that students taught physics using computer-supported Jigsaw II performed better than those taught using individualized computer instruction. In addition, students exposed to Jigsaw II cooperative learning strategy had positive attitude to physics than those taught with ICI. However, students’ gender had no influence on their performance. Based on the findings, it was recommended among other physics teachers should be encouraged to use computer-supported cooperative instructional strategy to improve students’ cognitive and affective outcomes.