This dissertation examines the relationship between principal leadership behaviors and student achievement in middle schools in Illinois. The purpose of this quantitative study was to determine the relationship between teachers' perceptions of Transformational Leadership and Instructional Leadership principal behaviors and the growth of student achievement in English Language Arts and math as measured by students meeting expectations on standardized testing from 2016 to 2019. The study utilized attitudinal measures of teachers regarding principals from the 2019 5Essentials Survey. The three primary research frameworks explored the relationship between student achievement and the Effective Leaders composite rating on the 5Essentials Survey, the Effective Leaders subcategory ratings (Program Coherence, Teacher-Principal Trust, Instructional Leadership, and Teacher Influence), and the 24 individual survey questions within the Effective Leaders category. Findings from this study demonstrated teachers' perceptions of the effectiveness of the principal were not positively associated with student achievement. In fact, this study indicated the opposite: as student academic growth increased, the teacher ratings of the principal decreased. This study suggests that if principals are improving student achievement, teachers will not always positively value and embrace the leader. Implications for practice include the necessity for caution when using annual teacher surveys to measure principal effectiveness on student achievement and the influence on student achievement when principals lead within the framework of a "Connected Driver." Principals who are "Connected Drivers" are able to connect deeply with their staff while simultaneously driving the staff toward the ultimate goal of education, which is the improvement of student achievement. [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.]