restrict users

Having used Asus-Merlin, I don't think I've had problems like this before. Knowing how successful everyone else were with their updates, I'm more frustrated at myself more than anything. Every time I do some maintenance from replacing filters for reverse osmosis tank to updating router...

Is there a way to require students to log in by user name/ID to access the internet at a private school. We currently have no budget to set up a full blown server / workstation system. We need to track student's online activity as well as restrict access to only necessary websites...