There is a resounding push for education to be equitable and effective for all students, including students with disabilities--a subgroup of students that fall under the special education categorization. In public schools nationwide, historically students with disabilities have underperformed when compared to their non-disabled peers (American Institute for Research [AIR], 2012). Students with disabilities, for example, graduate from high school at lower rates and are less likely to be gainfully employed (Tomasello, 2018). Despite protections under the law that ensures that students with disabilities will receive a free, appropriate public education in the least restrictive environment (Tomasello, 2018), students with disabilities still struggle to be as successful as their non-disabled peers. The gaps in achievement between students with disabilities and students without disabilities is a reminder of the inequity that exist within the U.S. system of public education. The achievement of students who receive special education is chronically low and below that of their general education peers (AIR, 2012). To increase the number of students with disabilities that are college and career ready, the achievement of students with disabilities must improve (Tomasello, 2018). Research has shown that the most effective SDI approaches are rooted in EBPs due to their tendency of having a meaningful effect on student outcomes (Cook & Odom, 2013). Nevertheless, school districts and schools still struggle to implement effective SDI as the academic and post-secondary achievement data of students with disabilities shows (CEC & CEEDAR, 2017).The CEC and CEEDAR (2017) have highlighted that improved student achievement is causally linked to effective teacher practice. Hattie (2009) revealed that student achievement is influenced by instructional leadership, specifically, the feedback and demonstration and modeling of effective teaching practices that school leaders provide for teachers. The Professional Learning Standards (2015) have called for school leaders to investigate the correlation between teacher practice and student performance. The arguments from Hattie (2009) and the Professional Learning Standards (2015) suggest that school leaders can positively influence teachers' effectiveness, which subsequently will improve students' learning outcomes (Hattie, 2009; NPBEA, 2015). Based on the perspective that school leaders influence teacher practice and student achievement, school leaders' knowledge of SDI can directly shape the implementation of SDIs in their schools (CEC & CEEDAR, 2017; Crocket, 2002; Hattie, 2009; NPBEA, 2015; Sugai, 2013; Zaretsky, et al., 2008). [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.]