Depending on budget,
An evening at Cirque, my girls both LOVED this show and constantly ask when they can go back.
An Illuminations cruise to Epcot, this can work out quite inexpensive if you canfind a family to share the cost of the cruise with as the boats take 12 I think.
My girls enjoyed meals at AKL then explore the hotel and the animal "savannahs, but by the time the women folk get ready to go out after a day in the parks/pool ypu're not going to have an enourmous amount of time to fill.
By the time you add in park days/night and a couple of shopping trips I doubt you'll have too much time to worry about filling in time. If you're in a hotel they can always swim late then get something to eat, if you're in a villa by the time you eat and let them watch TV for an hour they'll be ready for bed.