I think an Aqua Cat would be a great boat for kids.

Here are two links, one to American Sail, which manufactures the boat, and you can learn more there about both of the Aqua Cat models. And the other link is to a magazine article.

www.americansail.com/
http://www.sailingonline.com/fullby0201.html

Personally, I recommend the Hobie Wave, but you could have a lot of fun with the Aqua Cat, too. And it is probably lighter weight.

As with any cat, follow the advice that has been given on this forum to check for soft hulls and other problems. They started making Aqua Cats 48 years ago, so some of them are ancient. On the other hand, they are still making and selling them, so those could be relatively young boats.