Purpose and Method of Study: The purpose of this study was to compare the effectiveness of two approaches to professional development methodologies implemented in public schools. A quantitative, correlational research design was employed to determine whether the academic success in the core content areas of reading, writing, math and science could be predicted by a school district's PDS or PDSN/PDN partnerships with universities and Colleges of Education, or by a district's traditional approach to professional development. Participants included elementary school students in third through fifth grades attending eight elementary schools in two Central and Northeast Central Florida school districts from the 2006-2007 through the 2016-2017 school year. The data collection instruments were the two mandated annual achievement assessments, the Florida Comprehensive Achievement Test (FCAT) and Florida Standards Assessment (FSA). Data analysis was conducted through the SPSS software program. The study's four hypotheses were separated into predetermined steps based on the Hierarchical Linear Regression analysis methodology, the formula for the Florida School Grading Statute, and best practices based in research. Findings and Conclusions: This study investigated all measurable categories included within the Florida School Grading Statutes, while considering the community variables of socioeconomic, school and district racial make-ups, and student mobility in order to compare the investigated schools and districts. Although this study and its completed analyses were not able to predict or identify a direct correlation between the type of professional development and student achievement, the predictive models indicate a strong relationship between purposeful professional development and student achievement. These findings have implications for both further practice and research as practitioners and researchers identify, investigate, and implement complete and meaningful professional development opportunities to provide teachers with the skills, strategies and knowledge needed to provide the best instruction and support possible to address all school level factors, while increasing the achievement of all students within the K-20 education settings. [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.]