An important focus in Indigenous education research focuses on equitable educational experiences to support student outcomes. This study explored the implementation of a mathematics education initiative in an Australian Indigenous community school aimed at raising students’ mathematics proficiency over a 7-month period. The initiative was informed by current scholarship focused on effective practices in mathematics education, and explored how teachers implemented a mathematics education initiative, and factors that influenced the development of students’ mathematical proficiency. To achieve the aims of the study, an innovative conceptual framework was developed integrating perspectives from sociology and psychology. A mixed methods research design was used, and data sources included standardised mathematics tests, adapted classroom diagnostic tests, problem-solving interviews, and classroom observations. The participants in the study included 50 primary school students (Years two to six) and four primary school teachers. Findings from the study indicated that students’ mathematical proficiency was below national means at the beginning of the initiative. At the end of the study, positive changes in students’ proficiency were found, with evidence of closing gaps in achievement noted on some measures (i.e., on standardised tests). Other findings indicated there were complex factors associated with students, teachers, the school, cultural-factors, and community factors that acted to influence the development of students’ mathematical proficiency. The findings inform curriculum recommendations including the need for early years mathematics programs to focus on key number concepts, as well as the inclusion of problem-solving heuristics into problem-solving programs. The importance of supporting Indigenous students’ productive dispositions towards mathematics, developing skills for success at school in the early years, and considering interpersonal interactions when assessing students was also highlighted in the study findings. Teaching practice recommendations include the use of balanced explicit instruction, a diagnostic teaching cycle with effective and immediate feedback, a mastery teaching approach, consistent lesson structures, and an expectation of high academic and behavioural standards with increased time on task. The findings support the value of mentoring models of professional development to support teachers’ capacity with pedagogical content knowledge, in addition to the need to focus on developing Indigenous students’ familiarity with the school discourse to enable them to engage successfully with this discourse in the early primary years.