We cruised Alaska on the Carnival Spirit last summer and our kids (then age 7 and 3) had a BLAST in Camp Carnival. Our 3 yr old daughter cried every time we had to pick her up
We had a suite (catagory 11) and had plenty of room and a balcony. DO NOT cruise Alaska without a balcony!!!!! You'll miss so much scenery if you do.
The cruise was very child friendly and the staff was wonderful.
We will be cruising with Carnival again in March 2007 for the Western Caribbean and can't wait. The kids are so excited about going back to camp, it's cracking us up!!!!
Good luck with your decision and enjoy the cruise