Understanding children’s physical activity (PA) patterns and the factors that may influence PA are important for developing interventions within this population. One hundred and ten children aged 9–0 years from 8 schools had their PA patterns assessed over 7 days. Physiological and self-report data were also collected. Multilevel analyses revealed that cardiorespiratory fitness was a consistent, significant and positive predictor of weekday and weekend PA, while the availability of home sedentary activities was a significant but negative predictor of PA. Since a range of variables were associated with PA levels, intervention developers should be cognizant of variables that may influence children’s activity.