The purpose of this study was to examine the effects of performance-contingent rewards in a real-world setting, namely the sixth grade math classroom. This study is significant in that it represents a field study on the effects of rewards in the classroom. The purpose of this study was to investigate what effect, if any, the choice of a reward had on students' self-reported perceptions of competence, autonomous regulation, and intrinsic motivation, as well as seatwork scores and achievement over time. Sixty-six students from an urban sixth grade middle school were randomly assigned to one of two conditions (choice versus no choice of a reward) and completed measures of perceptions of competence, autonomy, and motivation at one, two, three, and seven weeks. In addition, seatwork was collected each week for a total of four seatwork assignments and scored. Pre and post achievement measures were also collected. Overall, the findings were found to be largely inconclusive. Initial findings indicated that having a choice to be rewarded increased perceptions of intrinsic motivation. However, further analysis found that statistically significant differences were present between the two groups before the treatment was introduced. Thus, increase in intrinsic motivation could not be attributed to having a choice to be rewarded. Results also did not support an increase in the perceptions of autonomy or competence when offered a choice. Furthermore, no statistically significant achievement differences were found by condition. In short, no substantial evidence was found in favor of or against reward use in the present study. How the factors of competence, autonomy, and intrinsic motivation interact in the face of rewards and how this interaction affects academic achievement in whole classrooms remains ambiguous. Implications for both General Interest Theory and Cognitive Evaluation Theory are discussed. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]