By CNN Staff
(CNN) -- In a rare move for the first lady, Michelle Obama is expected to step into a public dispute with Congressional Republicans Tuesday as the House considers major changes to the 2010 nutrition bill - a hallmark of her "Let's Move" campaign against childhood obesity.
Obama will hold a meeting with school leaders and experts to emphasize a need "to protect and advance" the progress Washington has made in school nutrition programs, according to the White House. She's set to make brief remarks before reporters during part of the meeting.
The House Appropriations Committee announced last week it plans to let cash-strapped schools opt out of the nutrition regulations via waiver. The change would come through the 2015 agriculture spending bill.
Signed into law in 2010, the nutrition bill established new requirements for the country's free or reduced-price lunch program. More than 30 million children qualify for the federally subsidized meals.
New standards included a reduction in sodium and a requirement that each student choose one fruit or vegetable in order to get the meal for free.
The law increased the reimbursement rate for school lunches as a way to help offset the higher cost of including more produce products.
Critics, however, say schools are struggling to keep up with the new rules.
"We've experienced a lot more food waste," Julia Bauscher, president-elect of the School Nutrition Association, said Tuesday on CNN's "Newsroom."
"Students will pick up what they're supposed to have at the end of the line and then immediately throw it in the garbage," she said, describing trash cans full of oranges and apples.
Bauscher said they're not advocating for a return of junk food to the school lunch line-just looser requirements on vegetables and fruits.
"We just don't want them to have to take it if they don't intend to consume it," she added.
CNN's Ashley Killough contributed to this report.
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