Having mastered the 30-minute meal and daytime television, Rachael Ray is on to her next challenge – childhood obesity.

With help from former President Bill Clinton, the celebrity chef known for cutesy phrases and a fast, freewheeling cooking style now is launching a charitable group that aims to help children eat healthier at home and in school.

Ray says The Yum-o! Organization (the name is drawn from one of her signature phrases) will work with schools to improve cafeteria food, create scholarships, educate parents about healthy eating and help fund charitable groups that feed needy children.

The school food overhaul – which Ray and Clinton announced April 26 on her syndicated talk show – involves teaming with the Alliance for a Healthier Generation, an effort by Clinton and the American Heart Association to clean up school food.

“Great food changes the entire quality of your life,” says Ray, who taped the episode of “Rachael Ray” earlier in April. “It’s just this great building block for families.”

Working with Ray is part of the Alliance’s overall strategy of enlisting celebrities (others include NBA players and musicians) to help make healthy eating hip for children, says Bob Harrison, the group’s executive director.

Harrison, whose 2-year-old group already is working with about 1,000 schools and hopes to be in 30,000 after four years, called Ray a trusted name in the food world who can help get the Alliance’s message to parents.

Some in the public health community – which is grappling with a nation in which nearly 1 in 5 children is overweight – are intrigued by the influence Ray’s celebrity could bring to the struggle against obesity.

Celebrity involvement can prompt action, says Dr. A. Mark Fendrick, a University of Michigan School of Public Health professor who found that former “Today” show host Katie Couric’s televised colonoscopy increased appointments for the procedure 20 percent.

There is, however, a difference between making an appointment for a procedure and making lasting lifestyle changes. And though Fendrick thinks it certainly will help, he says it has yet to be seen whether the celebrity factor can overcome that sort of inertia.

Nevertheless, the news was welcomed by Dr. David Ludwig, an obesity specialist at Children’s Hospital Boston who says notable personalities until now haven’t taken up the childhood obesity battle.

That change is a sign that obesity is being taken more seriously and Ludwig thinks the publicity could have significant influence.

Ray says her plan was inspired by the efforts of other food celebrities, including Jamie Oliver (who led a televised crusade to revamp England’s school lunches) and Alice Waters (whose Edible Schoolyard program in Berkeley, Calif., helps schools serve healthy food).

And she is borrowing from Paul Newman’s philanthropic model, which donates the profits of his food products to charity. Ray is developing various products, including children’s cookware and books, the profits from which will go to The Yum-o! Organization.

The group’s budget still is being developed, but Ray expects to spend close to $750,000 of her own money launching Yum-o! this year, and has pledged to cover any fundraising shortfalls in the future.

“It’s a blank check as far as I’m concerned,” Ray says of the proceeds, as well as the seed money she provided to launch the organization. “I have no idea what it’s cost so far. I don’t care. As long as the check doesn’t bounce.”

Solutions to obesity have proved elusive, largely because they require major lifestyle changes and the causes are so multifaceted.

Ray and Harrison believe the key to success is getting parents to consider healthy cooking something easily woven into overscheduled lives, as well as getting children to consider it cool to eat good-for-you foods.

Both messages will become regular fodder on Ray’s talk show, and form the core of Yum-o!’s Web site, http://www.yum-o.org/.

Much of The Yum-o! Organization’s work will be pursued via existing programs.

For Ray, this is the realization of a longtime wish to help people with little time and money eat right.