Hi K!
Art of Animation is such a beautiful resort, you'll want to head back and spend some downtime there. It's in a great location that is pretty much centrally located between the parks, so traveling to and from isn't that big of a time taker.
Landscape of Flavors, the food court, has a variety of delicious dining options and is one of the few restaurants that still carries the thick crust whole wheat pizza...my fave! Grab lunch and head to the pool for some relaxation and downtime.
Be sure to check the daily activities at your resort. My 5 year old loves the afternoon pool games at the resorts. This is a great way to let your kids have some fun outside of the parks and let them have a little freedom.
My best tip for not overwhelming the kids is to be patient parents. I am a go-go-go type of Mom, but had to learn how to slow down while visiting Walt Disney World. Don't cram too much into the schedule and leave some room for some unexpected magic along the way, meaning it's ok to veer off course a little. Let your kids do some of the planning so they have something personal to look forward to, like a favorite ride or visiting a favorite character.
Have a magical day!
Leslie