My son is rather picky. He doesn't like lunchmeat sandwiches or cold cheese.
He usually took peanut butter and jelly or a thermos of chicken noodle, vegetable soup, spaghetti o's.
Then some type of fruit or veggie: carrot sticks, grapes, a banana, apple slices, mandarin oranges, blueberries, applesauce, etc.
Then some other snack. Yogurt, pretzels, goldfish, granola bars, cheerios, pudding, etc.
A juice box or his water bottle filled with water.
On rare occasions I would add a fruit roll up or a fruit snack as a special treat.
I agree on helping out the little ones. I would work in the cafeteria sometimes and that was all I did was open stuff for them. I bought mostly large bags of stuff and big containers of things like yogurt and then put them in small containers that were easy to open. I got those glad snack sized ones and my son never had a problem with them.