As part of the Assessing the New Federalism project, this report investigates the different types of child care arrangements, including unsupervised "self-care" that families with working mothers use for their school-age children. The study investigated how child care patterns differ by the age of the child, family income, race and ethnicity, parental time available, whether the mother works traditional versus nontraditional hours, and by state. The report uses data from the 1997 National Survey of America's Families to investigate child care patterns for children aged to 12. Of the nonparental child care arrangements, before- and after-school programs and relatives are the most commonly reported among 6-to 9-year-olds, with 21% of children in this age group in each of these forms of care while the mother is working. Five percent of 6-to-9-year-olds have self-care as their primary child care arrangement while the parent is working, and overall, 10% of children in this age group regularly spend any time in self-care. Like younger children, a significant percentage of 10-to-12-year-olds rely on relatives as the primary caregiver (17%), but smaller percentages of these children are in before- and after-school care. Twenty-four percent of the children in this age group have self-care as their primary form of care while the mother is working, and 35% of children in this age group regularly spend any time in self-care each week. Children from lower income families spend more time in their primary child care arrangement each week. In the younger age group, Black children are more likely to spend time in before- and after-school programs than Hispanic children, but, among 10-to-12-year-olds, White children are twice as likely as Hispanic children and almost three times as likely as Black children to use self-care as the primary form of care. Appendixes contain a discussion of the child care patterns for 5-year-olds and the standard error and sample size tables. (Contains 9 figures, 11 tables, 20 endnotes, and 17 references.) (SLD)