Site Blocking
If you allow your kids to go online on their own, use the built-in the windows content blocker. It allows you to specify which sites you do not allow them to access blocking entry with a password or to totally prevent entry 
to a site by blocking it altogether. There are facilities where you list the web site�s address which prevents your browser from entering the site and risking your information getting stolen by intruders who manage to get in when you are away and your kid is at the helm. Often they use the computer at the same time if you have several kids making the gap bigger and opportunities for intruders getting in.