I do about the twice the amount of food you do as well for my school age kids. I have a 6yo, a 7yo and an 8yo. They usually have a yogurt and whole piece of fruit. Or a granola bar and piece of fruit. They do eat their lunches at school (my own 7yo will eat a sandwich, cheese & crackers, apple, carrot sticks, and a pudding a school) but they come home so hungry afterwards. They eat their snack and then dinner too...school takes a lot out of them, IMO!

My rule here is that if you eat your yogurt/granola bar/fruit cup/cheese&crackers then you get an apple. They can always have an apple. Inexpensive, wholesome, and if they are full at least they are full of apple. LOL.

ETA: My afterschoolers are two girls and a boy. I also do snack as 'family style'...if it's cut up fruit or cheese & crackers then it all gets put on a platter and the kids help themselves. Some eat more and some eat less.