What do I put in a kids’ lunch box?

[ChequersDog]

I don’t mean the pretend ‘two slices of avocado, six raw almonds and a handful of wild rice’ lunchboxes. I mean what do your actual existing 7-9 year-old eat? I’ve never done one before and DS needs one for a sports day camp. I guess it needs to be quite substantial. He says all the kids with packed lunches at school have sandwiches, crisps and a cake. Coincidentally that’s what he would like, so not sure how true it is.

7, 8 and 9 year old’s all have the same.
Sandwich/wrap, usually filled with cheese salad because they’re fussy and not keen on much else
frube type yogurt or a Tupperware filled with bio yogurt and fruit (this is a messier option though)
Packet of crisps/biscuits depending on the day
2 pieces of fruit
Dunker/babybel/cheese string-whichever is on offer
Cereal bar
Raisins

They eat all of that and still leave hungry. I’ve tried various other things that either go uneaten or again, still hungry. I always take a snack for them after school.

I don’t add a separate drink because they take a large water bottle to school every day.