Hawaii has a hotel /water park that is very family friendly sorry I can’t remember the name. Depending on where you are coming from there is Disneyland in Southern California or go all out and go the universal studios/Disney world in Florida. if you are looking for something more relaxing for the adults I would suggest renting a beach house with great views; that way they kids get to play in the sand and the parents get to relax. Have fun on your get-a-way!