Kubic, Kathryn LeighABSTRACT James County Public Schools was a 74,000 student school district in Maryland that chose to implement a pre-K - 12 aligned mathematics program in response to state mandated assessments imposed by the No Child Left Behind (NCLB) federal legislation. Schools that fail to demonstrate Adequate Yearly Progress on these assessments may descend into a spiral of sanctions. Consequently, districts must choose and implement programs that will increase student achievement. This study sought to determine the characteristics of the pre-K - 12 aligned mathematics program and explore and describe the dynamics of its implementation through the lens of a change facilitator. The study used a case study design methodology. The findings revealed the district implemented four parts of an instructional component: district assessments, pacing guides, professional development, and a single text adoption program. The change facilitator undertook activities to support the implementation. The study found three positive results of the implementation: Creation of Student Support Courses, Creation of a Benchmark Data System, and Creation of a University of Maryland Baltimore County (UMBC) Cohort. When the pace of the implementation was analyzed, conflict surrounded the implementation and it yielded three negative results: Competition for Scarce Resources, Defensive Professional Development, Trail of Memos, and Professional Blunders. The findings of this study added to the research and literature on implementation, particularly the role of the change facilitator. The findings also will assist other districts in policy and practice as they too seek to implement new instructional programs in their efforts to comply with the demands of NCLB.en-USA Case Study: Change Facilitator Activity to Support the Implementation of a District's Pre-K-12 Aligned Mathematics ProgramDissertationEducation, MathematicsEducation, Mathematicsalignmentcurriculumimplementationdistrictmathematics