I would plan on heading to the Penguin Encounter almost immediately upon opening, since they normally do the feeding then. Do Wild Arctic if your kids can handle a ride like Star Tours - otherwise, either do the non-simulation video, or just head into the exhibit.
Wild Arctic has a great kids play area with ice caves and such, and is a great walk through with lots of tactile things to do.
Definitely do a morning dolphin show, an afternoon Sea Lion show, and an evening Shamu show, if you can swing it. If you HAVE to skip one show, remember that none of the stadiums have shade, and only you know what animals your kids HAVE to see.
Remember that if the kids get wet at any of the exhibits or shows they're going to be sticky! So wet wipes and/or frequent arm washing is going to be a plus.
Don't forget the tide pool exhibit, and if your kids are set on seeing a sea star, ask the educator at the pool if they can get one of the stars for them to touch, if they're too far out of reach.
The play area in Sea World is fantastic, but tires kids out. Only you know when they'll need a break, or how long they can play for before being wiped out.
Take a time out for some food in a covered, shaded area, and STAY HYDRATED!!!! Especially with a beach day and Disneyland coming up, if the kids stop having fun, go find a shady place outside of the sesame street lights show (and the Cirque de La Mer stadium) lay some clothes out on the grass and relax. Trust me, your children will thank you by the time you get to Disneyland!
If you only get to feed one thing, I recommend the sting rays, as the dolphin feeding (unless your kids are dolphin CRAZY) tends to be a bit crazy and they'll easily be smushed, or disappointed if a dolphin takes their fish and doesn't stick around to be paid attention to.
Hope that helps.... Have a fantastic time!!!
B