Whatever educational level from kindergarten through to college. Is there anything you look back on with particular fondness, or horror? This covers meals provided on site, and meals brought from home.
In high school I usually brought lunch from home, and would supplement with treats bought at the canteen. I went through a phase that lasted at least two terms one year, where my lunch was a ham and cheese croissant that I made in a bunch on the weekend, then froze, and would take one to school every day but would eat at recess time instead of lunch, when it wasn't quite defrosted yet. I liked the coldness of the flaky pastry, and the slightly frozen texture of the ham and cheese within. I was sometimes a bit weird and disgusting, as a teen.
My favourite lolly (what us Australians call candy or sweets, in case you didn't know this irrelevant piece of trivia) were Pythons, which were jumbo sized multicolour jelly snakes. I irrationally felt that ones with a blue section tasted the best, and would specifically request "One with some blue in it please" to the canteen lady fishing it out of the Python jar.
There was a deep fried treat called a Chicken and Corn Roll, which was basically a chicken nugget plus some corn kernels, the size of a fish finger. They were pure mystery meat and sodium, and I loved them.
I remember some parents protested when our school introduced the Coke machines, but we got them anyway and it was very exciting.