WASHINGTON (AP) – Michelle Obama munched a baby turnip, dug up giant sweet potatoes and snipped pumpkins off the vine as she teamed up with local school children and a pair of world-class chefs for a late year harvest day in the White House garden.

One hulking sweet potato weighed in at four pounds on its own, drawing an admiring stare from the the first lady.

President Barack Obama's wife has made improving the eating habits of Americans a signature venture for her time in the White House. She established a White House garden and has reaped seasonal fruit and vegetables, much of it for use in the White House.

"You guys have witnessed the first White House pumpkins," the first lady told the children as they loaded up wheelbarrows and weighed in their haul.

Mrs. Obama later posed for a group photo with the harvest team, and at first prompted the children to smile and say "cheese".

But then she had a better idea, declaring, "Let's say `veggies!"'

After the kids finished their harvesting, they were put to work once again, washing the produce and then slicing and dicing vegetables for a fresh garden salad made just for them.

The White House kitchen team got some help from world renowned chefs Daniel Boulud, from Lyon, France, and New Yorker James Kent, representing the United States in the 2011 Bocuse d'Or cooking competition in Lyon, known informally as the Olympics of cooking.

Boulud quizzed the schoolkids on what to do with turnips and then told them: "We can make a good soup with that."

The garden has produced 1,600 pounds of food this year, used to feed the first family and White House guests and for donations.