ReadWriteWeb has a nice writeup on Glubble, a Firefox plugin for Parental control. It has some nice features including,
 Glubble lets you set up child accounts in two flavors: for kids who can read, and kids who can’t. The main difference is that the pre-read accounts, as they are called, don’t display a URL and search bar, so kids instead navigate by clicking on icons and links to pre-defined sites.
…
Glubble comes preloaded with a set of approved websites. These include kid friendly sites like Fisher Price, Barbie.com, Animal Planet, Disney, and Nickelodeon. It also appears that every site in the Yahoo! Kids Directory
is available for kids protected by Glubble (at least, every site I clicked on worked). Yahoo! Kids lists over 57,000 web sites in its directory, so there are a fair number to get started with.
So lock up your Internet Explorer and go Glubble.
Copacetic 
Are sites like Barbie.com kid friendly?
LikeLike
@ Johnny, to explain…
That’s the great thing about Glubble, you get to decide for yourself, it is not censorship.
If you don’t like barbie.com you can take it out, moreover when your child uses Glubble for Firefox on any other machine it synchronises so they get the same experience on any Firefox browser with Glubble installed.
All the best, Ian
LikeLike