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Kindergarten: Half Full or Half Empty?

States' kindergarten policies continue to diverge, despite years of research revealing the academic benefits of full-day kindergarten.

America's school districts are at odds over what seems a simple decision: whether to keep kindergarteners in school all day long or just for half-days. For decades, researchers have collected data to help guide principals and governments, and the issue still seems far from resolved.

A new Early Childhood Research Quarterly study adds to evidence that full-day programs improve children's literacy and shows that small classes may be even better for disadvantaged students.

For educators and academics, kindergarten is a crucial area of study because it provides a bridge between early learning and formal school. Most districts initially launched kindergarten as a half-day class, but full-day programs often replaced them as more parents began working full-time and children entered school after years in all-day preschool or day care. As recently as 1977, barely one-quarter of kindergarteners spent a full day in school. By 2001, that figure had jumped to 60 percent, and it is likely still growing. It's particularly prevalent in the South, as well as in public schools serving low-income families.

Despite additional costs in the low thousands of dollars per student, proponents tout full-day kindergarten's potential educational benefits: The longer day gives teachers more time to get to know kids and vary instruction methods, and children spend more hours learning. Academics have built a heap of research demonstrating that these advantages boost students' reading and math skills, even after they account for differences in race and income.

Keith Zvoch, University of Oregon professor and lead researcher on the new study, tracked reading skills among kindergarten students in a large Southwestern school district, using tests throughout the school year to increase their confidence in the data. The overall outcome was similar to previous studies: "Kids who are more disadvantaged show up, on day one, behind," Zvoch said. "Throughout the kindergarten year, they're able to close that achievement gap."

The study also showed that in full-day programs, smaller classes increased literacy growth, especially among the students in "disadvantaged" schools or in those serving mostly low-income children. If the researchers are right - and several said other studies have pointed toward similar conclusions - it would be helpful for schools revising kindergarten programs.

However, many schools run into the problem Zvoch found when he followed the kids through to first grade, as part of a to-be-published study. During the summer after their full-day kindergarten school year, many students in disadvantaged schools fell behind their peers once again. While this decay in literacy skills was faster than others had seen, it does fit a common trend: Within a few years, the benefits of full-day kindergarten often all but disappear.

While these declining effects cut against much of what researchers know about early childhood education, study after study has shown the same progression.

Some studies have shown long-term achievement gains for certain groups, such as children of non-English-speaking immigrants. But the lack of evidence for positive academic effects of full-day kindergarten weakens the case for a program that may carry high costs, especially in fast-growing states like Arizona and Nevada. Inconclusive results on behavioral development during full-day kindergarten - in teaching kids, for example, not to fight or argue - leave the programs open to further criticism.

Many scholars argue that the shortcomings aren't with full-day kindergarten but with what happens later, at home and in school.

"If you put kids in a specialized program and, when they're done, you throw them back into a regular program, why would you expect it to work?" asked Columbia University professor Douglas Ready. "During this full-day kindergarten period, they have an advantage. You take them out of it; they lose that advantage."

It's challenging to isolate the effects of the kindergarten programs from later grades, much less the external variables in children's lives. Because all the studies are based in the real world, a randomized trial producing conclusive, cause-and-effect results isn't possible.

"A lot of people want a bottom-line answer. ‘Does full-day kindergarten work? Yes or no.' It's just not that simple," said Vi-Nhuan Le, researcher at the think tank RAND.

Small wonder that state legislatures, often their states' chief education regulators, maintain wildly divergent kindergarten policies. Some require full-day programs, others encourage them with funding incentives and others dissuade school districts from implementing them, though most of the current proposals are in favor of full-day kindergarten programs, according to the National Conference of State Legislatures.

As they wait for better data, several areas remain largely unexplored: Detailed studies about what's happening inside kindergarten classrooms, though costly and time-consuming, might provide valuable information about teaching methods for full-day kindergarten and how it might aid social and other nonacademic skills. Others might examine how elementary school teachers can adapt their classes to build on the programs' gains, instead of watching them fade.

"There's a lot of compelling research that full-day kindergarten can have a huge benefit," said Indiana University professor Jonathan Plucker. "If we can reconfigure elementary school to take advantage, that could change everything."

Zvoch is among many who believe full-day kindergarten must be the first of many programs aimed at preventing at-risk students from falling behind.

"Full-day kindergarten isn't necessarily a vaccine. It's not like you go in and get a shot of full-day kindergarten, and it makes everything fine from then on," Zvoch said. "If you want to have disadvantaged kids keep pace, there has to be continued intervention."