Poisson rouge means red fish in French. Poissonrouge.com is one of the greatest web sites for kids that I have ever been to. Chances are it will keep about 75 percent of adults entertained for an hour or two as well. The site is simple, visit and click on anything to discover new areas. The site will seem endless as you or your children click through feature after feature. No keyboard skills are required and the site is so well designed that it will hardly seem like you are on a website at all.
Another great web site is Hero Machine. This one may at first seem like it is just for boys, but my 9-year-old daughter has spent her share of hours on it as well.