by David Crary

NEW YORK - In one classroom, a group of preschool teachers squatted on the floor, pretending to be cave-dwelling hunter-gatherers. Next door, another group ended a raucous musical game by placing their tambourines and drums atop their heads.

Silly business, to be sure, but part of an agenda of utmost seriousness: To spread the word that America's children need more time for freewheeling play at home and in their schools.

"We're all sad, and we're a little worried. ... We're sad about something missing in childhood," psychologist and author Michael Thompson told 900 early childhood educators from 22 states packed into an auditorium last week.

"We have to fight back," he declared. "We're going to fight for play."

After his keynote speech at New York's 92nd Street Y, the teachers dispersed into dozens of workshops, some lighthearted, some scholarly - but all supporting the case that creative, spontaneous play is both vital and endangered.

It's not a brand-new cause - two years ago it was endorsed by the American Academy of Pediatrics. But social changes and new demands on kids' spare time confront free-play advocates with an ever-moving target.

Among the speakers at last week's Wonderplay conference Y was Kathy Hirsh-Pasek, a Temple University psychologist who contends that lack of play in early childhood education "could be the next global warming."

Without ample opportunity for forms of play that foster innovation and creative thinking, she argues, America's children will be at a disadvantage in the global economy.

"Play equals learning," she said. "For too long we have divorced the two."

Some of the factors behind diminished play time have been evolving for decades, others are more recent. Added together, they have resulted in eight to 12 fewer hours of free play time per week for the average American child since the 1980s, experts say.

Among the key factors, according to Thompson:

- Parents' reluctance to let their kids play outside on their own, for fear of abduction or injury, and the companion trend of scheduling lessons, supervised sports and other structured activities that consume a large chunk of a child's non-school hours.

- More hours per week spent by kids watching TV, playing video games, using the Internet, communicating on cell phones.

- Shortening or eliminating recess at many schools - a trend so pronounced that the National PTA has launched a "Rescuing Recess" campaign.

- More emphasis on formal learning in preschool, more homework for elementary school students and more pressure from parents on young children to quickly acquire academic skills.

"Parents are more self-conscious and competitive than in the past," Thompson said. "They're pushing their kids to excel. ... Free play loses out."

The consequences are potentially dire, according to Thompson. He contends that diminished time to play freely with other children is producing a generation of socially inept young people and is a factor behind high rates of youth obesity, anxiety, attention-deficit disorder and depression.

Many families turn to organized sports as a principal non-school activity, but Thompson noted that this option doesn't necessary breed creativity and can lead to burnout for good young athletes and frustration for the less skilled.

Vivian Paley, a former kindergarten teacher at the University of Chicago Laboratory Schools and now an author and consultant, argues that the most vital form of play for young children involves fantasy and role-playing with their peers.

"They're inventing abstract thinking, before the world tells them what to think," Paley said in her speech to the conference. "It gets them thinking, 'I am intended to have my own ideas.'"

She worried that preschools, in the drive to prepare students for the academic challenges ahead, are reducing the opportunity for group fantasy play - and thus reducing children's chances to learn on their own about fairness, kindness and other social interactions.

"The theater of the young receives the least attention from those planning the curriculum of our nation's schools," Paley said. "This very activity is being dismantled in our schools to make room for early phonics. ... Preschoolers are being asked to practice being first graders."

Fretta Reitzes, director of the 92 Street Y's youth and family center, which serves more than 6,000 children, says many of the parents she sees are struggling to find the right balance for their kids' schedules, asking "How much is too much?"

Preschool teachers need to lead by example, Reitzes said.

"Bringing play back into the lives of children, it's not just OK," she said. "It's really good for them."