Ahoy, Dakota!
My family has enjoyed the benefits of Disney Cruise Line's Youth Clubs since our daughters were little. Our youngest had just turned two on our first Disney Cruise, and she had a great time in "it's a small world!" nursery. On our next cruise, our girls enjoyed time together in the Oceaneer Club/Oceaneer Lab.
The Oceaneer Club/Lab hours are typically the same each day, but can vary on port days. We recently sailed on the gorgeous Disney Fantasy, and I've looked back at the Personal Navigators (daily guides to all the activities and events on the ship) from our cruise to check operating hours. On our first afternoon onboard, the Oceaneer Club/Lab opened at noon, and was open until midnight, with a short break for the Guest Assembly Drill. On most days, the hours were 9am-Midnight. On our day in Cozumel, the clubs opened one hour earlier, at 8am, and when we visited Castaway Cay the Lab opened at 8:30am. Simply refer to your Personal Navigator each day to see the hours for your specific sailing.
While in
Castaway Cay (Disney's private island), the Oceaneer Club on the ship usually doesn't open until late afternoon, due to the fact that the Youth Counselors will be hosting a Youth Club right on the island! Scuttle's Cove is a sandy play area on the island where you can check your kids in (just like the Youth Clubs on the ship!) for supervised activities and a 1,200-square-foot soft wet deck area with pop jets and geysers! My kids loved spending time in Scuttle's Cove when they were little - it's tons of fun! Guests that choose to remain onboard will have access to the Oceaneer Lab for their little ones.
I hope this helps with your planning - let us know if you have further questions before you set sail with Captain Mickey!
Have a magical day - Diane W.