This article presents rates of participation in organized extracurricular activity by Canadian children and youth aged 6 to 17 years, and examines how these rates vary by sociodemographic and socio-economic characteristics. The data are from Cycle 4 of the National Longitudinal Survey of Children and Youth (2000/2001). The majority of children and youth (86%) participated in at least one extracurricular activity. Girls were more likely than boys to be involved in non-sport activities and in clubs or community groups. Young children who lived in urban areas and those who lived with two parents had relatively high rates of participation in extracurricular activities. Participation rose with family income for children aged 6 to 13, but not for 14- to 17-year-olds. Children of all ages in the Western provinces had high participation rates in each type of activity; rates tended to be low in Quebec.