Any technical solution that is supposed to block teenagers from anything is not going to work very well, because you are facing an opponent that:
* is smarter than you,
* is very dedicated,
* has a lot of free time,
* has an extensive network of friends,
* faces no serious consequences if caught,
* outnumbers you,
* considers you an immoral crook.
You really, *really* want to have them on your side. That means education rather than control.