Orange wedges served with school-bought lunches turn into silly toys, wedged rind-side out in kids’ mouths like cartoon character lips.

Crunched juice pouches and milk boxes scatter the tables; half-eaten homemade sandwiches on white bread and nibbled-upon hot-lunch quesadillas lay smashed and limp as elementary school children in Broomfield, Colo., make faces and giggle through mealtime, creating an ear-splitting din.

“It’s my birthday in six days,” announces Isaiah Carpio, 6, grinning and waving a Twizzler stick for emphasis.

Food is not the central focus of their time; play is.

Across the country, adults are consumed with food kids eat – and how to stem the growing tide of childhood obesity, which health experts say could cause today’s youngest generation to be the first to live shorter lives than their parents.

The dire prediction prompted former President Bill Clinton to hit the road recently on a school-to-school campaign aimed at promoting healthy eating.

Junk food, inactivity – and the vehicle that often makes those things attractive to kids, the almighty television – are largely being held to blame.

Instead of shirking responsibility, some in the children’s broadcast world have responded with healthy-eating campaigns of their own.

Have you seen Nickelodeon lately?

Drinking soda and juice boxes, from right, Daniel Morton, 10, Mitchell Britton, 11, Peter Appenzeller, 11, and C.J. Marrujo, 10, eat lunch at Emerald Elementary School in Broomfield, Colo.

The children’s cable network regularly airs two humorous public service announcements educating kids about hidden sugars and how to control flatulence through eating healthy. Last October, Nick went “dark” for an afternoon – airing nothing but a static message to viewers – to promote the first Worldwide Day of Play.

And on “Sesame Street,” Cookie Monster has learned that cookies are “sometimes” food.

The question is: Can these efforts truly make a difference when children are barraged with ads aimed at them for sugary cereals, sodas and salty chips and snack food?

Margaret Campbell, associate professor of marketing at the University of Colorado, says she hopes they can.

“It’s hard for one ad to have a large impact,” Campbell says. “What definitely has an impact is consistent messages that are seen repeatedly and begin to shape children’s views of what’s right.”

A study released in February 2004 by the Kaiser Family Foundation showed a clear link between media and childhood obesity. Children who spend the most time with media are more likely to be overweight, the study says. The culprit, however, it says, is not that TV, video games and other media replace physical activity. Instead, the study fingers advertising.

A typical child sees about 40,000 ads a year on TV, the majority with the aim of selling them candy, cereal, soda and fast food. The American Psychological Assn. says what complicates matters is that children younger than 8 are unable to distinguish between commercials and regular programming and do not understand “persuasive intent” like older children do.

“Young children are uniquely vulnerable to commercial persuasion,” says Dale Kunkel, who co-authored the APA study.

The APA supports government regulation of such advertising, which might mean banning the airing of such ads during programming aimed at children younger than 8. Many child-advocacy groups agree.

“Young children when they see their favorite movie or TV show character with a product, it encourages them to want a product that they might not think about or notice otherwise,” says Patti Miller, of the media program for ChildrenNow, a children’s media advocacy group.

“If SpongeBob was advertising milk and carrots instead of fast food, it would make a difference.”

At PBS, the effects of advertising on children has never been an issue, since the network does not air traditional commercials.

Emily Westbrook, 8, eats a tortilla chip after finishing her sandwich while eating lunch at Emerald Elementary School.

Even so, the producers of the PBS staple, “Sesame Street,” acknowledge the influence the show’s characters have on their young audience and are putting it to work to promote healthy eating. Most notably, the Cookie Monster has learned to mix some veggies into his diet.

This season “Sesame Street” focuses on health as well as its standards: literacy, science and teaching numbers and counting.

“Cookie Monster will always be Cookie Monster. That’s who he is. But he’s learned moderation,” says Ray Hammerman, director of publicity for Sesame Workshop.

Hammerman says the show’s producers have received many positive letters. Even those who haven’t seen Cookie Monster and the “Sesame Street” gang munching on carrots and broccoli love the idea.

“Good,” says Tom Conroy, of Broomfield, whose 7-year-old, Kallie, is so picky she won’t eat bread, let alone most veggies. “Every little thing helps.”

That’s the attitude at Nickelodeon, which has zeroed in on childhood obesity and is working to promote healthy eating and exercise with entertaining programming and campaigns.

Last summer the network launched “LazyTown,” a show designed to make physical fitness entertaining for preschoolers. The main character, Sportacus, is played by show creator Magnus Scheving, a professional athlete and aerobic champion in Iceland.

Its Let’s Just Play campaign, which involves Boys & Girls Clubs of America and the National PTA, has awarded more than $600,000 in grants to 81 U.S. schools and non-profit organizations as part of its 2004-2005 program to create and expand opportunities for physical play.

The Worldwide Day of Play, which will be Oct. 1 this year, is an extension of the program.

Let’s Just Play is promoted through Nickelodeon’s Web site, magazines and on-air messages, and includes support from celebrities including Denzel Washington, Hilary Duff, Tiki Barber, Jamie Lynn Spears and Romeo.

“We are an entertainment company that believes we have a responsibility that extends beyond entertainment,” says Marva Smalls, executive vice president, Nickelodeon Networks public affairs.

Even so, Nickelodeon airs numerous commercials for candy, fast food, sugary cereals and the like. And shouldn’t all children’s entertainment companies balance social responsibility with shareholder interests?

Perhaps, says Campbell.

But Wall Street rules.

“It’s a difficult position for somebody like a Frito Lay to solve both duties,” Campbell says. The answer, she says, may rest in legislation.

Campbell says she questions whether it’s OK to bombard children with advertising messages before they’re able to understand their intent. The difficulty in enforcing a ban on such ads for young children’s programming will be in products that have crossover appeal, such as Pokemon, where both 7 year olds and 9 year olds enjoy the content.

“Obviously, I’m pro marketing,” says Campbell, who has two children, ages 8 and 12. “I just think it needs to be regulated and families need to help kids … You and I can make decisions about whether we want to eat at McDonald’s and whether we want ice cream. Kids don’t understand the persuasive component. They want the toy.”