Sandwich or wrap on white, with some protein, so that might be ham, cheese, smoked salmon (not trimmings but they love the stuff and I like them to eat it so don't really care about the cost, a couple of slices and I can scoff the rest, no harm done)
Ribena plus. Don't give a shit its full of aspartame (not full of, as you only need a drop to make it sweet, and don't buy the marketing about added vitamins, they are just affordable, the right size, etc)
Sometimes a penguin/tunnocks/gingerbread men minis, sometimes some peppers and cucumbers, or Ryvita minis sour cream and chive flavour
And a fruit without fail, be it a Satsuma (hate peeling them so great for school
, grapes, apple, pear, etc.
Our head is a boyatch about some things but not terribly about lunches as we pay for them, and provide them, so she feels not like dictating their contents though lollipops, haribo, full on chocolate etc gets frowned upon (i.e tell your parents we don't encourage that etc etc)
I tried hummus as my son loves it, but it felched itself all over the lunchbox, never again.
Banana skins drive me mad, but they make them take them home.
Don't do frubes. Pathological dislike of the things which always seem to squirt someone.
Anything I can assemble in less than 5 minutes in the morning works for me.