Included are all the food places on deck...chicken tenders, ice cream, fruit, burgers, pizza, etc. You can always get lemonade, coffee, ice water, etc. at no charge. Soda is included at the seated meals for dinner(or lunch if you go inside) but if you grab a soda at a bar, it is extra. All the food is included on
Castaway Cay. When the ship is in a port, you can return to the ship to eat and it is included. If you grab something on your own on the island, then you'll have to pay for that.
Anything you order from room service is included(unless you order cans of soda) But, you can take soda on board with you and not have to ever buy any. Gosh...it is easier to tell what is included than what isn't! If the kids eat with the kid's clubs, then that is included. If you go to the movies....included. Same with the live production shows.
Things that are not would be photographs the ship's photographer takes, if you choose to purchase them. Alcohol is not included. If you want to go off the ship and go to a beach, or go exploring...that you'll have to pay for. You have to figure in the cost of tips, which are not included in the fare. disneycruise.com has a list of the suggested tips. They do add up, so be sure to plan that into your budget. You'll find the servers do so much to make you happy that you'll want to give them that and more! There are shops onboard, and if you want to purchase things, that is also extra. The kids end up getting a souviner for free if they participate in so many of the activities. Mine got bucket hats last year. If they do the end of the week show, they will also receive a t shirt for free. Popcorn and sodas outside the movie theatre were not included. That is about all I can remember that isn't included in the cost.