WASHINGTON (AP) - Schoolchildren's favorite lunch - the ubiquitous frozen pizza - is about to get healthier.

First lady Michelle Obama and Agriculture Secretary Tom Vilsack are expected to announce Wednesday that most school meals will have less sodium, more whole grains and more fruits and vegetables as sides. The popular pizzas will still be on school lunch lines but made with healthier ingredients.

Mrs. Obama and Vilsack are appearing at an elementary school in Alexandria, Va., with celebrity chef Rachael Ray.

The new rules represent the first major nutritional overhaul of school meals in 15 years. They won't be as aggressive as the Obama administration had hoped. Congress last year blocked the USDA from
making some of the changes the department had sought, including
limiting french fries and pizzas.

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