Although research has provided a substantial amount of information about key characteristics of effective school leaders, there is a growing need for continued improvement and reflective practice on the continuous development of instructional leaders. The purpose of this study was to determine to what extent elementary principals perceive they are practicing the 21 leadership responsibility constructs, which research has shown have significant correlations to student achievement. This study focused on the relationship between student performance on the state communication arts assessment of students in grades three, four and five and the perceived level of competencies reported by responding elementary principals on the 21 leadership responsibility constructs. Of additional interest was the influence the intervening variables have on their leadership practice, the variables being: (1) adequate yearly progress (met/not met), (2) percent of free and reduced lunches, (3) school size, (4) principals' years of experience at the current school, (5) the principal's involvement in a professional learning community, and (6) gender. A questionnaire, based on the 21 leadership responsibility constructs, was electronically sent to all elementary principals in the state of Missouri that were responsible for educating students in grades three, four and five. Results of ANOVA and two-tailed t-tests indicated there were few differences between schools that met Adequate Yearly Progress and those that did not meet Adequate Yearly Progress, based on the intervening variables as they relate to the principals' practices of the 21 leadership responsibility constructs. Significant differences existed for the variable of gender for both schools that met Adequate Yearly Progress and schools that did not meet Adequate Yearly Progress, based on the intervening variables as they relate to the principals' practices of the 21 leadership responsibility constructs. Significant differences existed for the variable of gender for both schools that met Adequate Yearly Progress and schools that did not meet Adequate Yearly Progress that related to student achievement, with significant differences reported with gender. The results of this study can be used to help support reflective thought and dialogue about the 21 leadership responsibility constructs and the continued development of the craft of educational leadership in leading improved student performance. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]