This mixed-methods study examined what reform efforts are happening in high schools where students are demonstrating high academic growth, investigating the practices and behaviors principals are implementing within these schools, and determining if, and how, the six dimensions of PLCs (Hord, 1997; Hord & Tobia, 2012) are being implemented in these schools. This explanatory sequential design was based on the theoretical constructs of Professional Learning Communities (PLCs) (Hord, 1997; Hord & Tobia, 2012) and the 21 Leadership Responsibilities (Marzano, Waters, & McNulty, 20005). Nine principals completed both the Professional Learning Community Assessment ��� Revised (PLCA-R) (Olivier & Hipp, 2010; Olivier, Hipp, & Huffman, 2003) and the Balanced Leadership Questionnaire (Marzano et al., 2005). Descriptive statistical methods were used to analyze survey data and the interview questions were informed and grounded in the results of both surveys. Five principals participated in semi-structured interviews. The findings supported four reform efforts which included building a purposeful community, high expectations for all, shared and supportive leadership, and a focus on teaching and learning are each contributing to the student academic growth within these high schools. Additionally, the leadership practices and behaviors principals utilized were consistent with the 21 Leadership Responsibilities (Marzano et al., 2005) and the six dimensions of PLCs (Hord, 1997; Hord & Tobia, 2012) are being implemented in these schools. Both the leadership responsibilities and the dimensions of PLCs (Hord, 1997; Hord & Tobia, 2012) contributed to the student academic growth in these schools.