Changes in American society and education over the last 20 years have contributed to the popularity of all-day, every-day kindergarten programs. Full-day kindergarten is popular for a number of reasons. Full-day programs eliminate the need to provide buses and crossing guards at mid-day. In high-poverty schools, state and federal funding for at-risk students is often used to supplement all-day funding. Most important, research studies confirm that attendance in full-day kindergarten results in academic and social benefits for students, at least in the primary grades. One study found that full-day kindergartners exhibited more independent learning, classroom involvement, productivity in work with peers, and reflectiveness than did half-day kindergartners. However, observers of trends in kindergarten scheduling argue that the issue underlying the value of kindergarten programs is that of creating developmentally appropriate learning environments for all kindergarten children, regardless of the length of the school day. Developmentally appropriate, child-centered, all-day programs: (1) integrate new learning with past experience through project work, mixed-ability grouping, and mixed-age grouping; (2) involve children in first-hand experience; (3) emphasize language development; (4) work with parents to share information about their children; (5) offer a balance of small group, large group, and individual activities; (6) assess students' progress through close teacher observation; and (7) develop children's social skills. Contains 13 references. (BC)