Guys, any idea? Software na commonly used in schools/offices that will block certain commands/applications, also websites na pwede i-access. Is there a free software na ganon? If it should be bought, how much kaya ang going rate?

Functions should:
- Limit certain users in deleting internet cache/history
- Admin should be the only one who can install/uninstall applications
- Block websites

Sa school namin before naman, parang may spy software. Example, the prof suspects that STUDENT A using COMPUTER 1 is just playing Farmville, he will check on him by simply click the computer number of the student and he can see through what he's doing, parang spectator mode.