I have cruised with my kids, now ages 11 and 13 for years on Carnival, NCL, and Royal Carribbean. It's funny, when the kids were younger, they really liked the kids programs. Then they went through a stage where they didn't like it. I always signed them up, though, in case they decided to try something. They usually have "Family Games" on the days at sea, where we would all participate together, like scavenger hunts, etc.
The kids also liked going to the shows in the main auditorium every night. We had fun going to the photo gallery at night and finding our pictures, or watching one of the movies in our cabin. We always did the dinner in the main dining room, so that takes time just getting ready for.
On this last cruise, my teenager just loved hanging out in the teen section. Of course, she had an older cousin that she hung out with, but I hardly ever saw her during the day, she was having so much fun. It was great to see her so grown up, and having teen interests.
Feel free to ask me more questions. Have fun.
RCI Radiance of the Seas Sep 2009
NCL Sun March 2008
Carnival Destiny June 2006
Carnival Ecstasy June 2002
Carnival Elation August 2000
Celebrity Century June 1998
Carnival Carnivale August 1993