Probably some duplications here but here are some my kids like are mostly budget/healthy: cinnamon applesauce, jello w/ gummy worm in middle, pudding w/ cool whip, apples (since they are in season) cut up with caramel apple dip, grapes or other fruit w/ strawberry yogurt to dip, raisins, goldfish crackers, mickey shaped cheese, animal crackers w/ honey to dip, edible necklaces (like with cheerios or fruit loops), mini strawberry jelly/cream cheese sandwiches, popcorn, WW ice cream sandwiches- 1/4 graham cracker w/ ff cool whip frozen til set (my old bosses fav), mini rice cakes (I use pb with these, maybe flavored cream cheese or soybutter?), canned fruit drained in dixie cup, and 2 packs muffin mix prepared in 9x13 pan & cut in squares. My son likes to dip stuff, so you can omit if needed
. Some kids (like my dd) have texture issues, so maybe bring 2 options for the pickier eaters?
I've never had to bring anything to school except to parties & everything has to be packaged/ no homemade items, but I love bringing stuff. If you have the same rule, maybe you could bring a big container of whatever to school & prep in class (like pouring applesauce in cups). Like a previous poster mentioned, use the little dixie cups. They are cheap & you can use for snacks & drinks. I use a tray (like a lunch tray) & line up the cups, then pour in the jello or pudding & let it set in the cups, then put in the fridge. If you have a cupcake tupperware thing, the cups would probably fit in there, maybe put empty cups to fill up space if needed for taking to school.
I like the idea of bringing reusable plates since you will have to do on a monthly basis (if you have a dishwasher), CVS has cute summer themed plates 75% clearance right now. Cute little tea party plates might work too.