We were on the Celebration and they did have hairdryers in the bathrooms. I'm not sure about the shore excursions as we went to Cancun and Cozumel. Hubby was sick half the time and it was smack-dab in the middle of a hurricane, too so we didn't do much. I was also 7 months pregnant with our first child (we didn't know until AFTER we booked the cruise - LOL!) but we still had a good time!
We did the stingrays in Grand Cayman and it was fun. We did a swim with the dolphins in Cozumel (pre-hurricane) and it was awesome. The dolphins are incredible, they're so strong yet so gentle when interacting with humans. I think your children will really enjoy both of the activities. Have a wonderful cruise!!