When a child pays for school lunch next year, it will likely come with a lesson in economics.

Soaring food prices — triggered by forces including rising fuel costs and increased demand for wheat in China — have food service directors in area schools bracing for the worst price increases in years.

"I honestly can't say what percent," Beverly schools' food service director Martha Jo Fritz said of the increases. "But we know they're going up. We're all anticipating an increase."

Fritz leads a regional collaborative of 16 area school districts called Metro North, and the group plans to put out its annual bid March 31. Until the bids are returned, it's too early to tell how food quotes for next year's supplies will affect next year's lunch prices.

Metro North uses its collective buying power to reap cost savings for its individual districts. Together, they shop for five bulk items: paper and plastic (bid on together), grocery, milk, bread and ice cream, Fritz said.

The bids they release this month and choose from May 7 will lock in their prices for the next school year. Once chosen, a vendor can't break the contract without proof of drastic changes to his bottom line, she said.

"We pool our numbers and hope for the right bids that will encourage the vendor to give us great pricing," Fritz said.

Already, their vendors and distributors have warned them they're likely to pass along the increases they're seeing in fuel and other areas.

"Delivery costs are one of the main costs in the food-supply chain," said Danvers food service director Tom Powers. "Everything that travels to my food dock has traveled around the country, and fuel is very, very expensive."

He's sure prices are going to be higher.

"There's no question," he said.

Fritz said dairy products are affected by less corn feed and rising fuel costs. Oil also affects the cost of paper and plastic supplies, she said.

Flour prices have soared threefold in less than a year, said bakery owner Rob-Roy Quinzani of Quinzani's Bakery in Boston. His bakery supplies bread directly to all Boston, Stoughton and Walpole public schools through a distributor, he said.

"Schools haven't seen this coming," he said. "When the next bid comes out, there will be a much higher number."

Last spring, the bakery bought flour for $15 per unit. Now, it's $50, he said.

"Never in our lifetime or in my father's lifetime have we seen anything like that," said Quinzani, whose father and uncle started the family bakery in 1918.

Federal subsidies for ethanol have farmers choosing corn over other grains like wheat, he said. His broker informs him world demand for wheat is greater than ever with buyers from countries like China and India consuming greater portions of the supply.

"They're running out of the stuff, basically," he said. "We won't see any new crop until June."

Quinzani knows most cities and towns will be hard hit by the costs.

Peabody food services director Janyce Harkins said a number of school systems are already discussing increases to the cost of meals. It's not just food costs that are going up. It's labor, too, she said.

The Metro North collaborative hopes to keep costs down by building more flexibility into this year's bids. Fritz said the collaborative could opt for more generics.

For example, food service directors may know students prefer one brand of spaghetti sauce but will leave it to bidders to decide which type they sell.

If prices do go up, schools will have to try other ways to keep their costs down like using frozen fruits and vegetables in place of fresh produce, Fritz said.

Many districts track their meals to estimate what to prepare and how much. This reduces overproduction and waste, Fritz said.

"We really just try to serve what the kids will eat so we don't waste the food," she said.

But that may not be enough. Like other food preparers, they may have to increase lunch prices.

Metro North collaborative

Beverly, Boxford, Danvers, Georgetown, Hamilton-Wenham, Ipswich, Lynnfield, Manchester Essex, Marblehead, Middleton, Peabody, Pentucket, Rockport, Tewksbury, Topsfield and Wilmington.