Every summer, child advocates across the country warn of the consequences of summer vacation: brain drain, boredom and, most urgently, hunger.

More than 20 million American children rely on free or reduced-price school meals. When the last school bell rings, many of them don't know where their next meal is coming from.

There is a federal summer meals program for those who qualify for free or reduced-price lunch, but it's estimated to reach only 15 percent of eligible kids. The sites are often not convenient for families to get to, and some schools are opting out of summer meal programs altogether so they don't have to hire as much summer staff.

In Minneapolis, though, the free meals are served where the kids hang out.

Five years ago, the district retrofitted a school bus with refrigerators so it could drop off sandwiches, salads and fruits across the city. This year, it rolled out a food truck complete with grilling and cooking capabilities for hot meals. The menu for Street Eats -- as the truck is called -- changes weekly but has offered things like hamburgers, Philly cheesesteaks and Korean rice bowls.

The bus and truck drive around to eight sites across Minneapolis that are popular summer hangout spots but that don't offer food, places like libraries and parks. Each location gets the food bus four days a week and the food truck one day a week.

“Depending on the site, we see 45 to 100 kids at a single stop,” says Sara Eugene, culinary and wellness services coordinator for Minneapolis Public Schools.

At first, Eugene says, "the perception of seeing a food truck was a little confusing, but we really worked to get the word out that these really are free meals for kids."

The district is using a $75,000 grant from Cargill and the Super Bowl Legacy Fund for the food truck and the expanded food offerings. The overall summer food service program is part of the federally funded school meals program.

Swiss-Inspired Cafeteria Changes

This isn’t the only way Minneapolis has gotten creative about students' health. The person in charge of the school lunch program there, Bertrand Weber, hails from Switzerland and says he is appalled by the quality of food in Americans' school cafeterias.

He has rebranded the school districts' food department as "culinary and wellness services" and transitioned the cafeterias into cook-from-scratch kitchens, where all meals are cooked on-site and with ingredients from local farms and manufacturers.

“For the past 40 years, there’s been a reliance on pre-packaged meals -- even the fruits and veggies were pre-packaged. I wanted to bring back real foods,” Weber says.

Another change is bus routes. Buses will occasionally stop about a half a mile away from school, and a monitor escorts the children the rest of the way on foot. The kids get some good physical activity, and once they arrive at school they receive a grab-and-go breakfast.

“Everything we do, we think of it as more than just feeding the child because it takes a lot more than food to be healthy,” Weber says.

The shift away from pre-packaged meals is catching on elsewhere. Comprehensive statistics aren’t available, but a number of school districts, including Spokane, Wash.; Boulder and Denver, Colo.; have moved to scratch cooking in their cafeterias in recent years.

The next challenge for these school districts, according to Weber, is proving to restaurant-level chefs that schools meals are more than just reheated pizza and chicken fingers.

"As we switch to a culinary model, the challenge is still in being able to attract real culinary professionals," says Weber. "There's still this perception that school food isn't good."