How old our your kids?
When DD started preshool last year I was totally clueless! But now I'm an old pro. I don't send anything that needs to be heated as they don't do that. They also, send home whatever your child doesn't eat, so that you can monitor what they are and are not eating. So without further ado......
PB&J sandwich or just lunch meat/no bread. Ham or Salami
Drink ~ Choc. Milk or juice pouch thing
Yougurt or Gogurt
Fruit ~ grapes, babanas or an apple
and other varies things:
Cheese & crackers or Peanut Butter & Crackers
It just depends on if she ask for something in particular or what I happen to grab. Funny thing is, she only eats about half her chips and usually brings home any junk food (cookies). I don't expect her to eat it all ~ She is only 3, but I want her to have choices. Like I said, they send home leftovers, so that I can modify what I send.
Hope this helps