In 1994, approximately 95% of American five-year-olds were enrolled in school, primarily in kindergarten programs. At least 39 states currently require local education agencies to make kindergarten available to their residents; of these, 26 states offer half-day programs and 13 states offer full-day programs. Given such extensive participation, together with the acknowledged importance of children’s early years for setting future paths, it is surprising that educators are not in greater agreement about the importance of full-day kindergarten.

This Spotlight provides an overview of research comparing half-day with full-day kindergarten programs, focusing particular attention on the “strength” of the findings; that is, does research demonstrate definitively that full-day kindergartens are or are not superior? Before turning research findings into policy decisions, however, another question must be addressed, namely: What can we reasonably expect to achieve through kindergarten participation?

RESEARCH COMPARING FULL- AND HALF-DAY PROGRAMS

Over the past several decades, numerous investigations have compared half-day with full-day kindergartens. Reviews summarizing this work have also been published (Karweit, 1989). Findings from the research indicate consistently that full-day kindergarten programs seem most effective on short-term measures for disadvantaged populations. Although long-term effects were found only rarely, no study found differences in favor of half-day. In addition, several studies found that, regardless of the curriculum, low-socioeconomic (SES) students benefited more greatly from full-day kindergarten than middle- or high-SES students.

Fewer studies on the topic have been conducted since 1990, but they do provide other useful information. These studies indicate that parents favor a full-day program that reduces the number of “transitions” that kindergartners experience, and that families who are not able to schedule both child care and kindergarten find full-day kindergartens especially attractive. If these are predominantly low-income families, their children may reap particular advantages from the full-day programs.

One more recent study of kindergarten schedules stands out because, using very large samples, it examined a diverse set of short-term and long-term outcomes (Cryan, Sheehan, Wiechel, & Bandy-Hedden, 1992). With cooperation from the Ohio Department of Education, the researchers analyzed two sets of data to study the effects of different kindergarten schedules (half-day; alternate day; full-day) and prior preschool experience. The results were consistent, indicating that participation in full-day kindergarten is positively related to subsequent school performance. Positive effects were found for both standardized test performance and grade retentions. The report notes further that there was no “interaction” with preschool attendance; that is, the positive effects of kindergarten were obtained for youngsters who had and those who had not attended preschool.

In addition to academic performance, behavior data were collected for a subsample of students who participated in the study. Significant differences favored full-day kindergarten children on all academic engagement scales and several of the social dimensions. The finding for academic engagement is particularly noteworthy given the importance of these behaviors for learning, and because they set the stage for behavior patterns and achievement over the years to come (Finn, 1989).

LIMITATIONS OF THE RESEARCH

With the many positive findings favoring full-day kindergarten, it might seem that the issue is settled, at least from a research point of view. This is not the case, for much of the research is limited in ways that reduce its utility for making policy decisions. Three limitations require particular attention.

First, in spite of the fact that questions about early schooling are particularly germane to students at risk, few studies give explicit attention to the effects of racial/ethnic identity or poverty on young children. Furthermore, too few have attempted to separate the effects of kindergarten from other early activities (e.g., educational support provided at home; daycare and preschool participation). Well-designed research is still needed to determine the extent to which early educational experiences can reduce the achievement gaps between students with greater and lesser degrees of educational need.

Second, studies of kindergarten schedules rarely document how time is allocated in half-day and full-day programs. This is fundamental if we want to be confident that the benefits of full-day kindergarten cannot be obtained at lower (half-day) cost. The question of the amount of time in school cannot be separated from that of how the time is used. The superiority of full-day kindergartens rests largely on their ability to increase the time students are actively engaged in learning.

The most pervasive and in many ways the most serious limitation, however, is “methodological:” the failure of most research to implement adequate scientific controls. In many studies, students were observed or tested after they were already enrolled in kindergarten. The implication of this is that the apparent outcomes of kindergarten may have resulted from other “confounding” factors. Children who attend full-day kindergartens may have participated disproportionately in preschool programs. More significantly, schools or districts that have the resources to support full-day programs may serve wealthier families—families that provide a wide range of other educational services to their children—and may provide more stimulating instruction as well. While it may appear that full-day kindergartens are having a positive impact, the “real” causes of improved performance may be a network of advantages available to some children that begin in their earliest years.

The only scientific technique for comparing the two programs definitively is an experiment in which children are assigned at random to half-day or full-day kindergartens that are similar except for schedule.

Given that we are not 100% confident of a causal relationship between kindergarten schedule and academic achievement and behavior, what can be concluded about the effectiveness of full-day kindergartens? In spite of the limitations, the data may be persuasive:

• A great deal of research has been completed on the topic.

• All of the research examining full-day kindergarten for disadvantaged children reveals benefits.

• No study has been identified in which half-day kindergarten produced greater learning than full-day kindergarten.

• Studies that attempt to control or limit selection bias in populations attending half- or full-day programs continue to find benefits of full-day.

It is very likely that (a) there are significant short-term academic benefits for students at risk attending full-day, as compared with half-day, kindergarten; and (b) learning behaviors that persevere are affected as well. While it is probable that the benefits carry into subsequent years, research has not consistently documented carryover effects beyond the first grade.

EXPECTATIONS OF FULL-DAY KINDERGARTEN

The objectives of kindergarten programs are not that different from those of other early-year efforts, namely:

• The development of children’s cognitive skills, including, but not limited to, skills necessary for reading and basic concepts of numeracy.

• The development of a set of engagement behaviors needed to benefit from instruction during kindergarten and in subsequent years.

• The development of a repertory of social behaviors that foster determine interactions with teachers and school staff, and with other students.

If full-day kindergarten is superior to half-day, research should be able to demonstrate its superiority in promoting each of these goals. With some qualifications, it has. That long-term consequences of full-day kindergarten have not been clearly demonstrated does not detract from the finding of important immediate and short-term benefits.

Researchers have also raised the possibility that, through full-day kindergartens, pupils can attain an increased set of expectations. For example, there is clear evidence that pupils can learn to read in kindergarten and that there are long-term benefits that follow; the increased time of full-day kindergartens may make reading accessible to a greater number of pupils. And we need not be held back by “models of inadequacy;” that is, by the assumption that students at risk cannot learn appropriate engagement behaviors, and thus improve their educational prognoses. Full-day kindergartens provide greater opportunity, but do not guarantee that pupils will be set on a positive trajectory.

Ultimately, the question of schedule is only part of the picture; the issue of content is even more significant. Research has documented a large variation in how time is spent in full-day programs, from some that amount to little more than babysitting to others that are filled with educationally-relevant activity. The absence of a stimulating program at an appropriate development level can only diminish any positive effects that might be realized. Further research to guide educators in designing and implementing such programs is imperative.

Cryan, J. R., Sheehan, R., Wiechel, J., & Bandy- Hedden, I. G. (1992). Success outcomes of full-day kindergarten: More positive behavior and increased achievement in the years after. Early Childhood Research Quarterly, 7, 187-203.

Finn, J. D. (1989). Withdrawing from school. Review of Educational Research, 59, 117-142.

Karweit, N. (1989). Effective kindergarten programs and practices for students at risk. In R. E. Slavin, N. L. Karweit, & N. A. Madden (Eds.), Effective programs for students at risk (pp. 103-142). Boston: Allyn & Bacon.