Absent a nationwide plan for universal public prekindergarten, states and districts have taken various approaches to increasing access to school-based educational opportunities for their youngest learners. Though some of these programs have focused on making public prekindergarten available to all families, others have targeted families most in need by introducing means-tested programs. Early efforts to expand access to public schooling for preschool-age children, such as the War on Poverty–era federal Head Start program, focused on reaching low-income children. More recently, states and cities have made significant investments in their own public preschool programs, often citing their utility in combatting racial, ethnic, and income-based test score differences that are apparent at school entry. (author abstract)