What are the ages of your kids?
If they're mostly over 10 and like thrills - Unversals Islands of Adventure is a fun place. Great roller coasters, water rides, thrill rides and some good shows. One of the lands is Seuss Landing. It's like you just walked into a Dr. Seuss book - really amazing.
Another fun place is Sea World. It has a good combination of shows (Killer Whale, Sea Lion and Otter, Dolphin and a great pet show), hands on places where you might be able to touch some of the sea life and they have a killer rollercoaster (Krakken) and a splash mountain type ride call Journey to Atlantis. Its a nice day because you do have long stretches of time to just sit (and wait for the shows to start and the shows that are mostly 20 to 30 minutes long)