Does anyone know of any open source projects or even proprietary software that would enable parental controls (i.e. blockage of porn sites) in Linux. My kids use Linux for the Internet and I don't want them stumbling onto something bad. There is lots of stuff for the Windows world, but not for Linux. Currently, I am just blocking sites with certain words via my router, but that is not protection enough. I did a search on some open source projects, but so far have not found anything. Any other advice as to how I could do this with scripts or other alternatives would be appreciated. Thanks!

Googling "linux internet parental control" turned up several likely solutions, some free, some not.

I have a personal aversion to any kind of content based blocking. My own primary prevention plan a few years ago when my kids were teenagers was to make sure computers stayed in a public area of the house. "Mistakes" like that don't happen nearly as often when a parent is likely to walk by the monitor.

You can try Squid or Dan's Guardian as a proxy server to block the content.

Dans Guardian looks like it should work well. We already do keep our machines out in open areas of the house and my 14 year old son has a good head on his shoulders. It is just that some of these porn sites lure people in through false links and I wish to eliminate that chance as much as possible. Gun sites are fine with me (Pro 2nd Amendment).