The experience of being on an enormous ship with seemingly infinite things to do is an incredible thrill for any kid. It's a feeling like being in the center of the world, with nothing to fear. A truly unique feeling.
A kid, if he's smart, knows that a cruise is much more relaxed and flexible than during a normal school week. For example, on a cruise, I believe that there should be no bed-time because even if they sleep ‘till noon, it's only their loss of time to swim, play video games, play Ping-Pong, go to programs, etc......
I know from experience that no adult should force a kid to go to a kid program if they don't want to. Some kids love them, some find them boring and uninteresting, so if they want to do anything else, let them! A good idea, however, is to go with your child to the first introductory program so that they can meet some of the other kids on the cruise. I know that some parents would feel a lot better if their child went to all programs so that they know where they are at all times, but, people like this really need to ease-up, because where are your kids going to go? Will they jump off the ship? (That was meant as a joke. If you really are worried about your kid jumping off the ship, then maybe it is a good idea to keep them in the programs, and seek them some help when you get home...).
Meal-time is also a really great time for a kid because there's the feeling of going to a restaurant every night, which they practically are. Let them order whatever they want. If they want to try something new, don't say that they won't like it, even if they won't. If it turns out that it tastes like a melted boot sprinkled with pond scum, they can always send it back and get some chicken fingers or something...
About a day or two into the cruise, your kid should find what they like and will likely stick to that activity quite constantly. If a kid spends the entire day in the pool, let him be! This means that they are having a great time and are enjoying every minute of this cruise. I don't care if they look like great, great, Grandpa' Jed after a month-long, scalding-hot shower. You let them stay in!
And finally, the arcade. If your kid is anything like me, they will immediately proceed with spending incredible amounts of money on "one last lap". From experience, I know that it's really disappointing to have a limit set on the amount of money I can spend. When my dad, Kuki (sure you've heard of him), sets a money limit on me, I cleverly negotiate with him (in parent speak: nag him) and finally get him to double the set limit. A good idea for you , is to double your set limit in your mind so that you can eliminate that oh-so-aggravating phase of the arcade experience. Trust me on this one.
Another thing that will usually make your kid very happy, is to join your child in the arcade. You can watch them, or better yet, play against them, and they will brighten up.
Thank you for coming on this guided tour of your kid's mind on cruising. I hope you learned something.