Letting your kids onto the World Wide Web

First off, it must be said that World Wide Web is an excellent term.

Ok.

My kids are getting older, and on a super fire sale I was able to get them some laptops. They currently use them supervised when on the internet, and school programs, and of course minecraft.

I was thinking though… could I whitelist just certain domains for when they are logged in, and then they can go to town on researching?

Is there an Encarta 95 filter to Wikipedia, for example?

Also, I am officially asking for anyones thoughts on this. Is censoring the internet for 8yrs and younger a bad thing? (I think not, but I want to hear opposing arguments!)