If the web filtering feature isn't working please go to a student device and open chrome and navigate to chrome://extensions. Check to make sure that you see both Netop Vision Student (the app that allows connectivity) and that the Netop Vision Student Extension (the actual web filter component) are both installed. If Netop Vision Student Extension is not installed, the web filter will not function correctly.

On the teacher machine, make sure that the URL's are defined correctly in the Web Filter text document.

You will want to put it in the following format:
 https://netop.com
 
http://netop.com
 
* This is done because the HTTP portion usually redirects to HTTPS.
* The www is also not needed
 * The more specific you are with the URL the tighter the restriction

Make sure that the 'Filter Web' is enabled as well. If not enabled, the pages you you white listed will not work. 

If you continue to have issues after making sure both extensions are installed please contact Netop Support.