When Deborah Gilboa's second-oldest son Nadav started coming home from first grade with discipline warnings from his teacher, Gilboa and her husband were perplexed. Nadav, who had just turned 6, had the same teacher in kindergarten and had rarely gotten into trouble.

So Gilboa, a family medicine doctor in Pittsburgh who consults at askdoctorg.com, and her husband sat down to ask their son what was going on. He had the answer right away.

"He said, 'In kindergarten we had recess twice a day and we went to gym twice a week,'" Gilboa told LiveScience. Now, as a first-grader, Nadav's class only went to gym once every six days. They had one recess period a day, split with lunch, so that Nadav had only about 15 minutes a day to run around.

"He said, 'I get this feeling in my legs when they want to run and that feeling moves up to my belly and when that feeling moves up to my head I can't remember what the rules are,'" Gilboa said. "So he had really noticed a big change in his own behavior and self-control."

For kids like Nadav, the transition from summer freedom to the grindstone of the classroom may be tough. With schools under pressure to meet standardized testing goals, recess has been cut back and even eliminated in some school districts. The irony, experts say, is that schools may be shooting themselves in the foot by taking away playtime that's crucial to a child's growth. [The Top 5 Benefits of Play]

An overall decrease in playtime in even young children is resulting in kids who don't have a "culture of play," said Jill Vialet, the founder of Playworks, a nonprofit dedicated to improving the climate of play in schools, teaching kids the kinds of games they would have once learned from older peers.

And Nadav isn't the only kid who finds that a school day without playtime makes sitting still tough: Kids who don't play much also tend to struggle with self-control and learning, experts say, which can haunt them throughout their lives.

"Play is really a developmentally significant experience," Vialet told LiveScience. "It helps kids become high-functioning citizens and grown-ups."

Goodbye, playtime

Children's free playtime has dropped over the years, replaced by structured activities and screen time, including television and computer use, studies suggest. A 2003 report by the Kaiser Family Foundation revealed that a quarter of kids under age 6 watched TV for at least two hours a day; these same kids spent 30 minutes less per day playing outside than kids who didn't spend so much time in front of a screen.

At the same time, unstructured childhood time is vanishing. A pair of University of Maryland studies of children's time use found that in 1981, kids ages 6 to 12 had about 57 hours of free time per week. By 2003, kids had only 48 hours in which to choose their own activities. Time spent outdoors was especially hard-hit.

Early schooling often exacerbates play's demise. A 2009 report by the Alliance for Childhood surveyed kindergartens in New York City and Los Angeles and found that children had less than 30 minutes a day, on average, of "choice" time, in which kids could do whatever they wanted. Kids in L.A. had only about 19 minutes of free time each day. The rest of the kindergarten day was filled with academics and standardized test preparation, the study found.

According to the American Association for the Child's Right to Play, as many as 40 percent of school districts in the United States have reduced recess in the aftermath of the No Child Left Behind act, which emphasizes testing scores.

These reductions tend to hit lower-income kids harder, experts say. In her practice, Gilboa sees children who get very little physical playtime during the day because of long school days and after-school programs that find it easier to keep an eye on kids who are watching movies rather than running around.

"Sixty minutes of vigorous physical activity a day prevents obesity in kids, and it used to be that between recess and gym you were getting that," Gilboa said. "This generation's kids would take that, but they're just not getting the opportunity."

Reclaiming recess

The result, experts say, is children who come into school without good play skills. Used to regimented activities, these kids may struggle with the give-and-take of playground games, said Kathy Hirsh-Pasek, a psychologist at Temple University. That's not a natural state, she told LiveScience.

"If kids were left to have some time on their own, they would in fact develop play," Hirsh-Pasek said. "Now what we do is, we endanger the species by taking play opportunities away from them."

Despite the increasing amount of academics schools are trying to cram into their day (a 2008 study published in The Elementary School Journal reported that up to a quarter of elementary schools don't even schedule recess regularly for all grade levels), some advocates are jumping in to improve kids' playground experiences. [Read: For Health, Recess as Good as Gym Class]

Playworks, founded by Vialet, is one example. Paid "play coaches" work at more than 300 low-income schools in 21 cities around the country, said Playworks spokesperson Cindy Wilson. These are schools in neighborhoods where street violence means kids don't get to roam freely outside, Wilson said.

"They don't have the opportunity to be outside and learn to play in the same way that many of us did, and that is by having the big kid on the playground that taught you the rules to the games," Wilson told LiveScience.

Playworks coaches teach classic playground games, Wilson said, and also teach kids ways to resolve disputes among themselves, like "roshambo," or paper-rock-scissors.

"When Isabelle and Aidan can resolve their own conflicts, the teacher doesn't have to do it, so that's big," Wilson said. A 2010-2011 survey of 2,591 teachers at Playworks schools conducted by the organization found that teachers reported reclaiming more than 24 hours of lost instructional time each year after the introduction of Playworks, because kids no longer needed as much help resolving fights.

Freedom and control

Another program, Tools of the Mind, guides play in the preschool years. Children in the program learn to plan their imaginative play and also take part in games such as "Simon Says," which help them learn behavioral control. While drawing out a "play plan" before engaging in a round of make-believe may seem odd, it's a helpful activity for the economically disadvantaged kids the program targets, said Laura Berk, a Illinois State University child development researcher who is not involved in the Tools of the Mind program.

"'Tools' has been a very, very successful program," Berk told LiveScience. "As a matter of fact, they have neuroscientists who have evaluated it and shown that children who experience that curricula compared to other preschool curricula make substantially greater gains in what we would call cognitive control, managing their attention, being able to inhibit an impulse and engage in a more thoughtful response."

While these guided programs have a place, child development experts also emphasize the need for kids to just be kids. That's a tough sell in schools trying to meet test guidelines set by the federal No Child Left Behind Act, said Olga Jarrett, a professor at Georgia State University who studies play and child development.

"Children ought to be able to choose their friends, choose their activities, choose even how active they're going to be during play," Jarrett told LiveScience. "It's through play that kids learn how to get along with other people and also learn to play with ideas. I worry about people that go through school with very little opportunity to really engage in that kind of play."

This article was reprinted with permission from LiveScience.

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