This project evaluated the feasibility of a child-centred 24-week physical activity intervention. The "Play5" strategy encourages children to choose to play vigorously five times a day for about as long as school recess. The seven-year-old children were randomised to control (n = 176) or intervention groups (n = 132). Data were collected at baseline and post-intervention. Programme evaluation included parent questionnaire, teacher records and a seven-day pedometer record with a sub-sample of children. The programme was successful in increasing vigorous activity (p = 0.04), but did not impact on moderate or sedentary activities. Young children were able to choose to be active without parent or teacher direction. (Contains 5 tables.)