This secondary data analysis examined the association of Head Start children's entry age and enrollment duration on children's dental, vision, and hearing health based on data from 60 local Head Start classrooms. Children were divided into three groups: One group of children entered Head Start at age three and maintained enrollment for one year (Group 1). The second group of children entered Head Start at age four and stayed one year (Group 2). The third group of children entered at age three and stayed in Head Start for two years (Group 3). Compared with Group 3, Group 1 had fewer dental problems and Group 2 had less identified hearing problems. Children's gender, ethnicity, and program characteristics and family risk factors were associated with health problems.