I just found more great tips!! The thread "Food for thought.." has a good discussion of food you don't want to miss. Also I found these I forgot to mention before:
preaddress labels for postcards (so i can leave the address book at home),
Buy your
Castaway Cay Postcards at Mickeys Mates, and fill them out prior to leaving the ship for Castaway Cay...drop them off at post office first thing ...you'll save time ....also, the post office sometimes runs out of post cards...you'll need some cash for postage, so don't forget...
Put your shirt on a hanger...hang it in the bathroom while you shower and wa-la, no wrinkles!
This from someone else - I put both pillowcases in a ziploc bag with four different colored Sharpies. I also slipped in a piece of paper with my kids names, their ages, and our stateroom number on it. I didn't make any specific requests. I walked it down to Guest Services the first night. I was told I would get it back by the end of the cruise. You can take a pillowcase or picture frame or whatever to guest services at the beginning of the cruise and leave it with Sharpies and request just princesses, Fab 6 or all the characters sign it
You can order all the desserts at dinner! and double desserts too!
If you put your children in the Oceaneer's lab, it is highly probable that may not be the place you pick them up. The kids are continually moved from place to place, or are in transition - in which case you have to wait for the entire bunch to be moved before you can begin the checkout process. This is also the case at Castaway Cay. When you go to get your kids, they may be in the middle of a treasure hunt, for example.
The lesson here is, you can't expect to pickup your kids at the last moment if you are hoping to be somewhere at an exact time.
- take your own pics at EVERY opportunity that the photogs do or ask them to take the pics -- we didn't buy one single photo from shutters because ours were identical!
before you leave, if you have extra supplies, ask your servers or host if they would like them. My servers practically jumped up and down at the prospect of getting my shoe organizer! I wound up giving her the organizer, humidifier, full size conditioner, lysol and room fresheners. The crew doesn't get off the ship much, so they're very appreciative!
kids get a t-shirt and Mickey ear graduation hats for free from the Kid's club the day before the cruise ends. they are no replacement to buying the "real" tshirts they sell in the stores and at Castaway Cay.
don't bring a white board or water bottles -- they give them away for free in the kids' clubs and Ocean Quest--(I have not verified this)

me being ocd at 1am!