What would be wrong with the parents providing stuff for the kids to pack a lunch with? Even at our poorest, I fenced on weekends or other days off in exchange for beef and antelope. Also cleaned ranchers houses (some were bachelor cow camps. some pretty awful.), nailed boards, put out thistle weevils, anything legal and moral. Out of that we made stews and sandwiches. I baked our bread as a treat.
Okay. Not everyone has access to rural work. But if money is that tight -- babysitting, house/yard cleaning, light home maintenance, etc. can all bring some income so you don't have to depend on the schools for yet one more thing with regard to a child.
Yeah, and definitely get kids moving more, in general.