There seems to be a lot of hysteria & worry around the Internet.
Oh, noes! They took away her lunch-box (they didn't)! Her lunch-box! That's crap!
Oh, noes! They made her eat chicken nuggets (they didn't)! Chicken nuggets! That's crap!
Oh, noes! They made her eat a portion of grain! A portion of grain! That's crap!
Oh, noes! They wanted to give her a carton of skimmed milk! Skimmed milk! That's crap!
Oh, noes! They wanted to give her a carton of chocolate milk! Chocolate milk! That's crap!
Is there too much fat in this Guacamole?
Is there too much omega-6 in this pork?
Is there too much BPA in this bottled water?
And so on...
Firstly, chicken nuggets, grains, skimmed milk and chocolate milk are not crap. They're not perfect, but they're far better than chocolate/candy bars and fizzy drinks.
Schools act in loco parentis, so they are not going to feed the children crap. USDA guidelines are nowhere near perfect, but children who aren't humongously fat are metabolically-flexible. Therefore, whether they eat carbohydrates or fats, their bodies will burn them. If a child has been diagnosed with Coeliac disease, they won't be given gluten grains (unless the school wants to get sued).
Eat some carbs, dammit. See Why I Ditched Low Carb.
To quote from The Hitchhiker's Guide to the Galaxy again, DON'T PANIC! The dose makes the poison. Dietary fructose is used by the liver to make blood glucose to run red blood cells & the brain. A non-keto-adapted brain uses ~140g/day of glucose. Therefore, in the absence of any other dietary carbohydrates, a child could eat 100g/day of fructose, or 200g/day of sucrose without harm. Obviously, other carbohydrates are being eaten, so the amount of fructose that can be eaten without harm is probably ~50g/day, or ~100g/day of sucrose, or ~90g/day of HFCS55.
Warning, irony alert. So, light up a large spliff and chill a bit! Here's a song to help.
EDIT: Worrying about "X" may be worse for you than "X" itself, due to the adverse effect of chronically-elevated cortisol.