By JENNY ANDERSON

Here is what $35,000 buys today: Steak and blue cheese tossed with dandelion greens. Artichoke, tomatoes and fennel with penne. Oven-roasted rutabaga fries.

And a rigorous education, to boot.

Parents who have wondered why New York private schooling costs so much have always been able to take solace in the fact that the cost of tuition usually covers lunch. But anyone who grew up eating Tater Tots counted out by lunch ladies might not recognize the cuisine now being served in some of New York City’s prep schools.

Many lunchrooms are run by professional chefs, who poll students on food preferences, survey consumption of squash varieties for menu planning and call students “clients.” Students at Friends Seminary eat locally sourced, grass-fed beef. Girls at Spence eat sesame Napa cabbage. Earlier this year, Dalton students welcomed Eric Schlosser, an alumnus and food activist, and Dan Barber, owner of the high-end farm-to-table Blue Hill restaurant, for a daylong food symposium. (Mario Batali worked the school into his schedule, too, but on a different day, parents said.) Discussions included food production in America and the perfect Moroccan merguez. Lunch, served family style, included roasted fennel salad with Parmesan frico, apple and red onion on frisée and faro with grilled vegetables and nebbiolo vinaigrette.

Public school menus have become a bit more creative, too: on the same day, students at nearby P.S. 198 and around the city were fed Tuscan roasted chicken, heart-shaped pretzels (it was Feb. 14) and French-cut green beans. Nonetheless, since they spend $1 per head — about a third of what private schools spend — and cook for hundreds of thousands of students in 1,700 schools, public schools are somewhat limited in just how haute they can be.

Eager to be cutting edge, many private schools use their lunchrooms to demonstrate health and eco-consciousness. At Friends Seminary, where the food program is run by Flik Independent Schools, a company that also services Horace Mann, Trinity and Dalton, menu design is an intricate dance that involves showcasing new, healthy foods, and carefully monitoring what kids do and do not like.

“It’s all a matter of introduction and exposure,” said Stefan Davenport, director of dining services at Friends Seminary. “Freshly prepared is night and day with frozen.”

At Friends, all the food is made fresh, of course, and more and more of it is locally sourced. Rather than a slab of sketchy beef on a white bun with deep-fried French fries, students are given grass-fed beef burgers on whole-wheat buns, with roasted potato wedges and fresh fruit for dessert. Vegetables are seasonal. The turkey is roasted in-house, as is the roast beef. All of it is nitrate-free, and the cafeteria itself is a certified green restaurant.

“The student body buys into us supporting local agriculture,” Mr. Davenport said.

Mystery meat is unheard of at the Calhoun School. A pig, killed in Vermont and wrapped in plastic, arrived on Thursday at the school, where students will cut it up in biology class, make head cheese, prosciutto and bacon, among other delicacies, in cooking class, and then eat them.

Lunch on Thursday included whole-wheat penne with pesto, two kinds of squash and a sandwich of tangy chicken salad on ciabatta bread. Students quickly devoured three kinds of apples. “I haven’t gone out to eat all year,” said Carner Round, a sophomore.

Nine years ago, Dorothy Hamilton, founder and C.E.O. of the French Culinary Institute and a Calhoun parent, suggested that the school hire Chef Bobo, a student of the Institute who wanted to focus his career on feeding healthy food to kids. Now a fixture at the school, Chef Bobo teaches a cooking class, runs a cooking club and blogs his recipes. Next year, he will teach a class in the politics of food.

“A lot of administrators think ‘It’s 30 minutes a day, what difference does it make?’ ” said the chef, known more conventionally as Robert Surles. “The theory here is that it’s part of the learning experience.”

Chef Bobo has consulted with at least a dozen other private schools, and three of his chefs — he has seven at Calhoun, all professionally trained — have gone on to other schools to run their food programs. “I hate to lose my chefs,” he said, “but I love to lose them to other schools.”

Professionally trained chefs and free-range, cage-free organic chicken eggs are not cheap. But neither is private school tuition, and some of the costs are offset by not paying overhead to institutional food providers, school heads and food consultants said.

“Zero-waste zones” are another popular goal, and where there is room, campus gardens and greenhouses are used to fill out the menu. At the Lawrenceville School near Princeton, N.J., Gary Giberson, director of dining and a founder of Sustainable Fare, a food-service company, has eliminated trays and reorganized the food staff so that cooks no longer spend their time scraping the students’ plates. Instead, they prepare entrees like seared pork loin pizzaiola and turkey-and-ricotta piadina with arugula. They are also composting 400 pounds of food waste a day on campus.

Of course the finest chefs in the world sometimes cannot compete with the teenage desire for freedom. Most private high schools have a take-it-or-leave-it lunch policy — the tuition is the same, regardless — and during one recent noon hour students from Sacred Heart and Nightingale-Bamford could be found at Yura, a cafe on 92nd and Madison. A few blocks east, other private school students and quite a few from Hunter College High School, the prestigious public school, were in the line at the Shake Shack.