This study was conducted in order to examine the effects of the Know-Want-Learn (KWL) strategy on 6th graders’ mathematics achievement, metacognitive skills and mathematics anxiety. A pretest-post test control group quasi- experimental design was used in the study. The sample of the study was composed of 55 6th graders attending public elementary schools. The data have been collected by administering the “Math Achievement Test”, “Metacognition Inventory” and the “Math Anxiety Scale”. The “KWL strategy” was used in teaching mathematics to the study group whereas the control group was taught using the “traditional method”. The results of the study showed that employing the “KWL strategy” in 6th grade mathematics can be effective in increasing achievement and metacognition while it was no efficient than the traditional method regarding the reduction of anxiety.