I've found a unique problem that no one seems to be asking quite the same question. Chat support didn't help at all so here I am.
Using the Comcast provided Xfi router, with the Parental Controls engaged through the web interface, then using the directions from the site to block specific sites through the 10.0.0.1 IP address I am trying to block youtube.com from my kids' school provided Chromebook laptops.
For whatever reason simply listing HTTP://youtube.com (and www.youtube.com and https://youtube.com and every other variation I could think of) and then having their Chromebooks checked as "no" under 'trusted devices' does not stop youtube from running on their devices.
But JUST youtube. And JUST those devices. I can block any other site on those devices - at least the ones I've tried. And I can block youtube on other devices in my house like my Roku TV, my new Chromecast, my own laptop, etc.
But what I really need to do is block it on the Chromebooks they use for school. Since they are provided by the school I do not have access to any settings on the devices themselves to install extensions or change the DNS settings or anything else. The school has been no help in blocking it from their side. So I need to block youtube from the router.
But it doesn't work. I don't know if Chromebooks use a different 'way' of going to the youtube site or something, but simply trying to block the URL doesn't work for the chromebooks.
PS. I've also just found that I cannot block it on our PS4. Not sure if that's related. But I'd like to block it there too.
I had the same issue. I blocked he following:
This works for blocking youtube on all devices (roku, ps4,xbox,chrome books etc).
However, I cannot get the trusted computer to work. Theoretically, trusting a device allows the device to bypass the restrictions. Trusted and Untrusted devices are blocked.
As I stated in my original post, I have tried all those permutations of youtube's URL and they work, just not on Chromebooks issued by the school (though I have no other Chromebooks to test) nor do they work on the PS4. The devices in question are set to 'no' under 'Trusted'.