In a north Texas school district, district administrators were concerned that mathematics scores at the target middle school have fallen below the state average since 2010. Despite professional development (PD) provided by the district, administrators believed that teachers were not using professional learning community (PLC) data reflection practices to improve mathematics performance. The purpose of this qualitative case study was to explore middle school teachers' as well as the administrative dean's perceptions of the levels of depth regarding teacher dialogue and collaboration related to mathematics instruction, classroom delivery strategies, data analysis of student performance, and lesson design within PLCs. The conceptual framework for this study centered on the characteristics of Senge's learning organization theory, Hord's PLC characteristics, and DuFour's model of collaboration for improving student achievement within PLCs. Six participants from the target school included 5 Grade 7 mathematics teachers and 1 administrative dean. Data were triangulated from interviews, observations, and archival documents and analyzed using comparative and inductive analyses. Themes supporting the findings indicated the teacher need for additional PD in the areas studied. Recommendations in the position paper include the evaluation of PLCs. The resulting project may deepen understanding of PLC needs related to data discussion, lesson planning, and may contribute to PLC or PD policy-related changes in the district. Enactment of the recommendations will improve PLC implementation strengthening teachers' collaboration and instructional skills resulting in positive social change and increased student mathematics performance.