This study assessed the feasibility and impact of introducing a programme of an additional 30 minutes per day of moderate physical activity within curriculum time on learning and readiness to learn in a large elementary school in south-east Queensland, Australia. The programme, Active Kids Active Minds (AKAM), involved Year 5 students (n = 107), their classroom teachers (n = 6) and an AKAM physical education specialist, and took place across one year. The fidelity of the intervention was assessed through objective physical activity measurement, while intervention outcomes included cognitive ability and self-perception tests as well as supplementary qualitative field observations, student academic records and behaviour records, and teacher and student participant interviews. Following the intervention, no significant changes were evident in students' cognition or self-perceptions. This paper reports the quantitative data measures that found only weak increased levels of moderate physical activity, qualitative results being reported elsewhere. The limitations and pragmatics around research design and physical activity interventions of this type in schools are also discussed.