E.W.
My family and I LOVE Rosehall Hilton and Spa Resort in Jamaica!! It is only an hour and a half flight from Dallas, and depending on the ages of your kids they can be free. They are also only 10-15 minutes from the airport and naturally have a free shuttle. They have a waterpark with a lazy river, slides, and everything on the resort and even have a swim up bar for mom and dad. If you have a Costco membership they have been the cheapest I have found to book through.
You will have a blast there. I have tons of pictures of the resort if you would like me to send them to you I would be happy to do it!