As an aside...
The 14 and 17 yr. old will be fine, but the 5 yr old will be a bear if you run him/her through the ringer of going to parks every day (especially given the heat you will experience in June). A cranky 5 yr. old can ruin a day in a hertbeat... so in everyone's best interest, I'd consider making sure he/she has some downtime at the hotel pool or something like that.

We just returned from a week in Orlando. One day at the parks, one day at the hotel, one day at the parks, one day at the hotel, etc, etc, etc. Worked wonderfully.