I have never been able to make AK a whole day park.
The first few times we went, we did not do midday breaks. We just went to the park and when we were done with it, we either went back to the hotel (we stayed off site the first few times) or parkhopped somewhere else. We would go to Magic Kingdom at open and stay till 10 or 11 PM. We would get to Epcot at open and leave anywhere from 7 PM to close. The latest we were at AK (again, without a midday break) was 3 or 4 PM.
Now, we stay onsite and do midday breaks. We will be at any given park until noon, 1 PM, 2 PM or so. Then go back to the room for a nap and back out to that park or another park, or just be done with the parks for the day and do something else. So AK is truly a half day park. We will only be there until 2 or 3, then we're done and we only do that one day of our entire trip. So we may have two different days where we go to DHS, 3 or 4 at Epcot, and 3 or 4 at MK, but all we do at AK is one day, half a day. We just can't find nearly as much to do there to keep us there very long, or to bring us back another day.
However, on our 2010 trip (our son's first trip), he got that stamp card where the kids get their cards stamped at each land, after seeing some kind of conservation spiel. He was excited about his stamps and he didn't get his card completed on our half day there. I wanted him to be able to get his card completed, so I saw to it that we worked in a few hours first thing on Saturday morning so he could get the rest of his stamps. We did, and I think we were out of there by noon. No matter how you cut it, we simply can't find enough to do there, nor do we have the interest in that park to do much more than a token half day visit.
