The study focused on the problem of poor academic performance in elementary schools by examining the relationship between principals' leadership behaviors and student achievement outcomes and the extent to which these behaviors differ according to the poverty and performance characteristics of the school. A review of the effective schools literature revealed that, second only to the classroom teacher, the school principal is the most critical individual in a school. The purpose of the study was to assess the relationship between elementary principals' self-reported instructional leadership behaviors (as measured by the Principal Instructional Management Rating Scale) and the level of student academic performance in grade 3 (as measured by the Georgia CRCT) in four classifications of schools: high poverty, low poverty, at or above the state performance average, and below the state performance average. Sixty-seven (67) elementary school principals representing a wide spectrum of the state participated in the study. The research was guided by seven research questions. The first five research questions were addressed by correlational procedures between elementary principals' self-reported leadership behaviors and student academic performance in grade 3 in each of the four types of schools. An independent sample t-test to assess differences in means was calculated for research questions 6 and 7. The study reported findings of the seven research questions with the implications of each. Conclusions emanated from findings that were statistically significant and those that were not. The summary of the findings indicated that there were no statistically significant relationship between elementary principals' instructional leadership behaviors and student academic performance. The findings also indicated that there were no statistically significant differences in elementary principals' instructional leadership behaviors and student academic performance. However, four instructional leadership subscales of the PIMRS were statistically significant and one instructional leadership subscale was statistically different. Because the other subscales scores were highly correlated, the lack of significance may be interpreted as reflecting the idea that they acted in concert with each other. The study concludes with an overall summary and recommendations. Recommendations for future research include replicating the study in other levels of schools with a larger number of respondents, as well as a mixed-method approach using teachers' perceptions of principals' instructional leadership. Further investigation into additional antecedent variables that influence the relationship between principals' instructional leadership and student academic performance is recommended as well as studying the passing rates of student subgroups. Also, since a significant relationship between principals' instructional leadership and student academic performance was not identified; it is recommended that future research investigate this relationship. [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.]