Does anyone know the cost for the Kids Club on DCL? Does the cost differ by age?

The cost is included in the price of your cruise.

The only exception is Flounders, which is for kids under 3, and those who are still in diapers. Flounders is considered group babysitting, and costs ~$5-10 an hour.

There are no program costs associated with the Oceaneers Club or Oceaneers Lab. Flounders Nursery is $6 per child per hour. There may be optional fees for some activites and extra snacks, but they aren't detailed on the Web site.

AVP

The only other costs are with the teen program if they want to go on special "teen-only" shore exursions. They'll give you a list of excursions ahead of time, and when you get on the ship you will get a complete list of activities (broken down by age).