Take a look at this yummy idea posted by Alicia over at bread & honey: Citrus-infused Campfire Cakes!
It's easypeasy: slice the tops off of oranges, hollow them out, plop in cake mix, stick the orange tops back on, wrap um up in foil, toss on the campfire, and let bake for around 5-10 minutes or so.
Kids will love these, and (at least for still-warmish CA) they're perfect for fall. Besides being tasty, the finished product is purty, too...the oranges sort of look like mini pumpkins, and lovely & mysterious blackened silhouette-type designs appear etched in the peel after some time in the heat. Beachy bonfire deliciousness!