The numbers vary from state to state, but there's no doubt there's a problem.
That's why the national school lunch program is upping efforts on healthy eating.
Kids get more than half of their calories from the cafeteria. Now that a lot of what's on the plate has changed, leaders are looking behind the menu of school lunches.
It's cafeteria time Terre Haute South High School.
But this lunch looks a little different from what you ate - from at least one serving of a fruit or vegetable per plate to a majority of products made from whole grains.
"It's critically important that we're prioritizing children's health. And since children do get so much of their good from school, that's a really great environment. So it is great news that so many schools are serving these healthy foods," said Jessica Donze Black, director of the Kids' Safe and Healthful Foods Project.
In Vigo County, the latest change is with portion size because they found servings were a bit too big. They're also cutting back on some of those greasy goods.
"Two years ago we'd have French fries three, four times a week at the high school level. Where now it might be once or twice," said Tom Lentes, food service coordinator for Vigo County Schools.
Even those times are changing.
Thanks to this new oven, most of the fries are baked.
Having those kind of tools in place is the next big hurdle.
Getting all Indiana school kitchens up to where it's near-perfect could cost $92 million. In many cases though -- including vigo -- what's needed are small-ticket items under $2,000.
"We're okay on refrigerators and freezers, it's gonna be the actual prep tools. And how can we slice apples better, how can we wedge oranges better...how can we do carrot sticks and celery sticks so it's fresh right from when we get it to then putting it out," said Lentes.
Or this sectionizer - an industrial-strength food chooper.
Experts have found students are more likely to eat fruits or veggies that are cut into pieces.
"So that little piece of equipment can make a big difference to how efficiently schools can serve meals," said Black.
Last month alone, Vigo County served more than 167,000 lunches. While the kitchens are keeping up, school leaders are always looking out for state and federal grants for any extra scraps.
"Food service never has been in need. But we can always use a new piece of equipment," said Lentes.
Looking down the road, it's all about freshness. Officials want to add a salad bar and a self-serve fresh fruit and vegetable table.
While lunch is the main school meal, what about breakfast?
The new healthy breakfast guidelines go into place at the start of next school year. The major change there's a new focus on fruit and grain instead of protein.
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