Hi Katie,
Thank you for your reply. The Norton DNS servers work properly. It's just very easy to bypass them, if you know what you are doing. For example, you can edit the wifi connection on a cell phone and remove the Norton DNS server ip address from the settings and change it to whatever DNS server ip address you want. The cell phone can then go to any web site using my router. I'm just trying to figure out a way to prevent that.
Thank you for your help.