This study investigates the effects of collaborative learning with or without metacognitive strategies on lower and higher achievers’ solution of geometry problems. Ninety-sevent students of grade eight (M = 13.7; SD = 0,6 year) from Indonesia were randomly allocated to participated in the study. Data analyzed by using qualitative and quantitative methods. Performance measures were collected on numerical and solving-problem abilities. Results in- dicated that studentswho were exposed to the metacognitive strategies within collaborative learning (COLAB+META) significantly outperformed their counterparts who were exposed to collabirative learning with no metacognitive instruction (COLAB). The experiment provided evidence that collabration be beneficial when learning under metacognitive strategies. Furthermore, the findings show the positive effects of COLAB+META method on lower and higher achievers.