Google: Force SafeSeaerch

SafeSearch Virtual IP address (VIP) will force all users on your network to use SafeSearch on Google Search while still allowing a secure connection via HTTPS. The VIP in SafeSearch VIP refers to a Virtual IP which is an IP address that can be routed internally to multiple Google servers.

When SafeSearch VIP is turned on, teachers and students at your school will see a notification the first time they go to Google; this will let them know that SafeSearch is on.

SafeSearch VIP can be used as part of a comprehensive internet safety policy by schools; this is part of keeping students secure while limiting their access to adult content at school.

Using SafeSearch VIP will not affect other Google services outside of Google Search.

To force SafeSearch for your network, you’ll need to update your DNS configuration. Set the DNS entry for www.google.com to be a CNAME for forcesafesearch.google.com.

Google will serve SafeSearch Search and Image Search results for requests that we receive on this VIP.


Reference:
Block adult content at your school
https://support.google.com/websearch/answer/186669?hl=en