Your kids will have a great time and there should be an abundant amount of friends for them to meet, as well. You will probably have vold weather for the first two days out and last two days back with the third day in each direction a transitional day. Don't worry though, there is tons to do on the ship itself.
Just in case though, I would take a notebook computer with speakers and a bunch of DVDs.
You can find out a lot about the ports by visiting this site
Let us know if you have any specific questions.