Big bowl of Pretzels to share
Icy poles(zooper dooper types ones)
I bake cookies or muffins or slices
I get a big watermelon and pre-cut it into a large bowl in the fridge, so its quicker to serve.
Crackers with vegemite, the homebrand crispbread type ones are cheap and there's a fair few in a box, plus the kids like the worms
We tend to eat at brekkie/morning tea/lunch/arvo tea/ dinner, not really grazing or snacking all day, but if they do ask for things inbetween then ice blocks or something not too filling are quick and easy to do and won't spoil a meal.