<p>Metacognition is a practice which enables students to monitor their thought processes in order to think critically. Research indicates that when students are aware of their thinking they become better thinkers. The purpose of this thesis is to encourage teachers to give more attention to metacognition in the classroom. A review of the literature on metacognition is given. Next, classroom lessons are outlined which introduce fourth grade students to metacognition in the context of math problem solving. Finally, an initial assessment is given of how students' metacognitive and problem solving abilities have changed as a results of the curriculum. Before the instruction began, all students were given a math problem solving pretest. A sample of nine students of different ability levels were given a pre-interview to assess their metacognitive abilities. Based on the pre-interview results, I realized that students were able to metacogitate to some degree, but that it needed to be fine-tuned. Students also demonstrated limited success solving the math word problems. After five weeks of instruction and practice, I gave a post-interview to the same nine students and the math problem solving posttest to all of the students. I measured the students' metacognitive growth and problem solving growth in several ways. There was evidence of an increase in student metacognitive and problem solving abilities in several areas, but two areas did not show substantial differences. I feel that one limit of the study was the five week time frame. It should have been extended. A question surfaced: Are student gains in problem solving ability due to metacognition instruction in the curriculum? Or are they caused by the problem solving instruction itself? A correlation analysis showed that improvement in metacognitive awareness was positively correlated with improvement in math problem solving ability. A future study was proposed to test the causal connection by comparing problem solving and intellectual gains in classrooms which either use or do not use metacognitive instruction.</p>