Absolutely!!
Get to the parks when they open and hang out until they start getting crowded or until just after lunch. Then take the bus back to your resort and get some pool time, or take a nap, or have lunch at the resort so you can see more at the park. Then after a two or three hours, head back to the parks to get some end of the day rides and fireworks.
It really is a whole new experience to be "On Property".