Roughly 30 million kids in the U.S. eat school lunch every day, and "Big Food" companies have a pretty big stake in what makes it on kids' trays. It starts with federal money, but before USDA funding makes it to cafeterias, many school districts order from food giants who grab a big slice of the school lunch pie.

Watch the video above for the history of school lunch and how our nation's kids are being fed today.