Staff development training is a method many public schools employ in an effort to prepare their teaching staff to better meet the demands of effectively educating district students. In this mixed methods case study quantitative and qualitative data was incorporated to answer four research questions: (1) How accurately do scores achieved by students on primary reading assessments of the Dynamic Indicators of Basic Early Literacy Skills predict the reading assessment levels they achieve as reported by the Grade Level 3 Pennsylvania System of School Assessment? (2) How do teachers perceive they are using assessment data and teaching strategies presented through their training initiatives to effectively adjust their instruction to meet student demands within their classrooms? (3) What perceptions do teachers share regarding the effectiveness of their district training programs in helping them meet the challenges of educating all their students? (4) What concepts of the roles of distributed leadership in their professional development programs do teachers share and do these roles reflect the three essential elements of distributed leadership: leadership practice is the central and anchoring concern; leadership practice is generated through the interaction of leaders, followers, and their situation, and the situation both defines leadership practice and is defined through leadership practice. The quantitative aspect of this case study incorporated statistical analysis of student assessment scores from three separate cohorts of students. Qualitative data was collected through teacher surveys and interview responses. Conclusions indicate that there was a predictive capacity between the DIBELS and PSSA assessments. Teachers perceived effectiveness in their training programs. They agreed that they have learned to use assessment data to more effectively adjust their instruction to the needs of their students. Teachers also perceived distributed leadership to play a role in their own professional development and that it is a crucial component in those staff trainings in which they have volunteered to participate. [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.]