You can block by name websites in your HOSTS file. https://www.google.com/#q=block+with+hosts+file finds many prior discussions on that.
The last time I used OpenDNS I had an admin login that unblocked sites.
All this really doesn't work if I change my DNS to say 8.8.8.8 and edit my hosts file. So a savvy user can easily get around your blocks. Is this a parental control question?
I want to block certain types of websites such as gaming sites from my home wifi network since I have kids who spend a lot of time in those gaming sites. I also want to restrict video streaming on certain computers. I have tried using the instructions given on this site: http://goxpctricks.atwebpages.com/opendns.php which worked for blocking sites, but it blocks websites for all devices on the network. I just want to block for certain computers only, not all computers on the network. Any idea on what I can do?

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