Since 2008, Australian students in Years 3, 5, 7 and 9 have been assessed through NAPLAN. In 2015, the Office of the Chief Scientist commissioned a study into the processes used by schools that demonstrated successful outcomes in NAPLAN numeracy. A team of researchers across Australia conducted a total of 55 case studies in order to identify practices and policies that were consistent between successful schools. Specifically the study sought to answer the following research questions: What system level influences are evident in schools with superior NAPLAN numeracy outcomes? What school level influences are evident in schools with superior NAPLAN numeracy outcomes? What classroom level influences are evident in schools with superior NAPLAN numeracy outcomes? What individual student influences are evident in schools with superior NAPLAN numeracy outcomes? Data were gathered through surveys, classroom observations and interviews conducted with school leaders, teachers, students, and parents. Overall findings indicated there were a number of characteristics that were common to schools who achieved sustained growth in NAPLAN results. These characteristics included the development and implementation of policies that specifically supported numeracy learning and teaching, use of a variety of data sources to develop and refine mathematics teaching programs, team planning, strong numeracy leadership and a consistent school approach to teaching mathematics. This paper presents the findings from three case study schools as illustrative examples of how the identified characteristics were enacted in practice, along with a number of recommendations that emerged from the data collected. The study has particular implications for policy makers and school leaders who may be seeking ways in which to develop consistent and effective mathematical practices in their own schools.