Concern is often raised about the performance of Australia's "best" mathematics students on international studies, relative to past students and other countries. An important consideration in developing strategies to ensure our most proficient mathematics students experience learning growth is an understanding of the distribution and concentration of high achieving students across schools, with subsequent implications for policy and teacher training. In this paper, student performance on the Numeracy test from the NAPLAN assessment is explored by grouping and comparing students at different levels of performance.