For years doctors, nutritionists and parents have deplored the eating habits of American kids.

Visionary chef Alice Waters is actually doing something about it.

The idea: the Edible Schoolyard, a one-acre garden where sixth-, seventh- and eighth- graders at a Berkeley, Calif., public school have learned to grow, prepare, serve and eat fresh food since 1995. The model for many similar programs around the country, the Edible Schoolyard has been re-created on the Mall as part of the Smithsonian Institution's annual Folklife Festival, which began last week and resumes tomorrow through the Fourth of July.

It started almost 20 years ago, when Waters regularly passed the Martin Luther King Jr. Middle School on her way home from her Berkeley restaurant, Chez Panisse. At night, the school looked abandoned, with graffiti on the windows and sunburned grass. She wondered how that had happened -- especially in a community-minded place such as Berkeley.

The school's principal, teachers and even the school board shared her concerns -- and Waters, well known even then for her commitment to fresh seasonal cooking, got an idea: A sad, unused acre on the eastern side of the school was a perfect place for a garden. It could be a learning lab where children could experience the pleasures of fresh food, from seed to table. It might woo them away from empty calories.

The garden should be organic, ecologically sound, beautiful and wholly integrated into the school's curriculum and lunch program.

Today, that acre is rich with seasonal produce, vines and berries, herbs, flowers and fruit trees. There's a chicken coop and a compost area, a place to start seedlings, a toolshed, a wood-fired oven, a picnic area and a central space for meetings and conversations.

"It worked," said Waters by phone recently. "When the children grew [food] and cooked it, they wanted to eat it."

At the Folklife Festival, the latest Edible Schoolyard sits comfortably on the Mall between the museums. There, the festival's organizers have planted a temporary 120-by-80 foot garden of artichokes and arugula, tomatoes and tatsoi, cucumbers and cabbage, herbs and okra, fruit trees and flowers.

"We've done quite a few plantings over the years" of the festival, says the program's co-curator, Stephen Kidd. "Cornfields, rice paddies. But this is our most ambitious, both in variety and size."

Seeds were started in the Smithsonian greenhouse. Children from local programs with a similar philosophy -- the Washington Youth Garden at the National Arboretum, Brainfood and the Smithsonian Early Enrichment Center -- helped plant the garden.

Docents -- including several teachers from the Martin Luther King Jr. schoolyard -- will be on the Mall to speak with festival-goers, who are encouraged to walk around the garden. Garden orientations are scheduled at 11 a.m. and 1 p.m. during the festival.

"It's an important place, right there on the Mall," Waters says. "I just hope we can use this to put a big public spotlight on education in America. "

Although the Edible Schoolyard was the first step in Waters's effort to transform American children's relationships with food, she is currently engrossed in what seems to her the logical next step: the School Lunch Initiative. The idea is to set up similar gardens at each of the Berkeley Unified School District's 16 schools and to make school lunch part of the curriculum -- a project initiated by the school board.

Waters doesn't mean giving academic credit for lunch -- at least not for now. Instead, the goal is to weave lunch into lesson plans for current subjects so that students understand what connects food, nature and real life.

As part of the state-mandated world history and geography curriculum, for example, students could grow, cook and eat foods from each culture they study. Grains grown in their school's garden could be harvested, threshed, winnowed and ground into flour as they might have been in Mesopotamia or Egypt or ancient Greece, and then cooked and eaten as a hot cereal. The cultural background would be part of history and geography, the measurements and calculations part of math, the actual planting and harvesting part of physical education. The school lunch plan is a long-term project. The first milestone will be a new kind of school cafeteria, where tables will be set with real dishes, glassware and cutlery. There, students and teachers will eat fresh seasonal breakfasts and lunches as they talk about the cultural, historical or culinary aspects of the food. The lead-off example, which is being set up at King Middle School, is scheduled to get underway in the fall of 2006.

Waters approaches the initiative with the zeal of the Montessori teacher she once was. "We're inventing a curriculum for a subject that has never been taught in the school system before," she says. "The most important thing is for pedagogy to be interactive, hands-on -- not where kids just sit in the classroom."

In the edible schoolyard, "they are moving, touching, smelling, getting an education of the senses. And when they do that, they open pathways into their minds."

Isn't the edible schoolyard a little idealistic, a little, "California"?

Waters says the children at the King school are like children at inner-city schools across the country. "Our kids are among the most disadvantaged," she says. "Many of them are getting free and reduced-cost lunches. There are 22 different languages spoken by the children here, and five different races.

"This isn't about the climate, either," she says. "People have gotten out of the habit of eating seasonally. We can eat beautiful, affordable things in season, but then we can cook or can them for future use."

She notes that it's expensive to run programs such as the Edible Schoolyard or the School Lunch Initiative. At King, the schoolyard has its own staff of eight. "You can't do this without having money to pay teachers," she says. She is uncompromising about the quality of ingredients. "I have to set the bar high, she says. "People have to understand they have to pay more for food. They're paying already with their own personal health."

"This country has a perverse, dysfunctional relationship with food," she says. "We think good food is only for the rich people. We don't have any understanding of the relationship of food to the environment, to culture or nature. We're educating a whole nation of youngsters with fast-food values. They're learning to waste. As a nation, we're not paying attention."

Karen Ellaurie, a volunteer with the Edible Schoolyard, plants lettuce for the Smithsonian Folklife Festival garden.John Carloftis puts finishing touches on the festival's ambitious schoolyard garden.