Once children start kindergarten, cupcakes aren't the only issue. The school cafeteria requires students as young as 5 to navigate entirely new options -- none of them controlled by their moms or dads.
School lunches, though far from perfect, have improved vastly over the past decade. Some 28 million hot lunches served to school kids each day are governed by the U.S. Department of Agriculture. By law, they must include milk, protein, fruits or vegetables, grains or breads, and no more than 30 percent of their calories may be from fat.
But to boost revenues, many schools offer additional items in the lunchroom. "My 5-year-old son had pizza as an option every day," says Kelli Rodda, of Azle, Texas. "Of course that's more appealing than chicken and vegetables."
And kids don't get much direction on what to choose. "When my kids started school, I was surprised to learn that teachers and lunchroom workers are prohibited by law from helping kids make choices," says Michelle Smith, a mother of two in Austin. "I always assumed that someone would say, 'Don't you think you should have a vegetable with that?' But even the youngest children are left to pick out their own meals."
Food sold outside the cafeteria can also make a healthy lunch less appealing. A report by the U.S. Government Accountability Office found that 46 percent of elementary schools have revenue-producing vending machines, sometimes stocked with soda, cookies, and chips. Snack carts and school stores offer more empty calories, and periodic fund-raisers often rely on baked goods or candy bars. Though such sales are usually prohibited during breakfast or lunch, they can still undermine a child's appetite.
Combine all those temptations with the candy many teachers give as rewards and the sharp decline in recess time and physical-education classes, and it's no wonder that so many American children are out of shape. While no one is blaming schools for America's high rate of childhood obesity (it's more than doubled over the past two decades), nutrition experts like Worobey are convinced that to reverse the trend, schools will have to become part of the solution.