I have an Irish applesauce cake recipe that uses chopped apples, besides the applesauce. It has a dense brownie consistency. My kids love it (as long as I leave the nuts out). If you're interested let me know and I'll type it in.
My kids also love "ants on a log" using apples, peanut butter (not necessarily safe at school...depends on the class/school) and dried cranberries.