Like others, ours LOVE watermelon. They love pretty much any fruit or veggie. They especially love peas, corn on the cob and zucchini. Since it's been so darned hot, I've been giving them a couple of bags of frozen veggies every day just for a cold treat.
Frozen watermelon rinds, frozen corn, tomatoes and grapes are some of my girls favorites. Oh, and my little OEGB loves bananas. I peel them and put them in a suet basket on the fence and she digs right in!