hi there, our first family flight was to DW in 04...we are also on the west coast, in bc,canada....at the time, my kids were 13,11 and 9....
OK, first day we were up and out of the house at 4:30 am (so woke the kids around 3:30 am) and were off driving to seattle for our hotel...Arrived in seattle in the afternoon and got to our hotel...kids were too excited, dont think they fell asleep til 10:30....OK, now up at 2:30 am for our 6 am flight....The best news, we hit the pop century at around 8 pm...(it was 5 pm our time)...kids again didnt get to bed til around 11, that is 8 our time, so they somewhat caught up a little...we hit the parks at opening next morning...they seemed to adjust better than my dh and i.....i get tired thinking of it

Hopefully your kids will sleep on the flight...and sleep in the day of your flight...they will probably just be on adrenline once you land....and get them in bed early the night u arrive...they can get a great nights rest...Have an awesome trip...
We are heading to DL in may and have to be up at 3:45 am for flight that day...will be in sunny california by 10:15 am, so worth it
sharon