parental controls's votes received   made
I sure do home slice, I'm not sure what you mean by parental controls but that's not what you should rely on.

Strong passwords and keys are not breakable by teenagers. Outside of Hogwarts that is.
Wrong ;)

On wifi a teenager is as easily blocked as anyone if you control your router and don't share the password, just block the site in question and you are done.

Most of us hold the purse-strings on our kids mobile subscriptions, credit card use, and control the mailbox keys in their house. Any help with this stuff just ask.

If they can get through all of that you have something functionally equivalent to an adult on your hands.

We've gone beyond security now and the remaining options are surveillance and parenting. I'll leave this dirty work to you all :)
how 2 control kids use of little biggy
guard the entry point
you can block littlebiggy.org at many levels of your device and network. if you need any help with your particular device use the thread below.

bitcoin barrier
even with your credit card in hand it's not so easy for kids to get bitcoins without ID and proof of residence in many places. only a very determined kid will get through this barrier.

last stand of defence: mail box
this is the critical point to block kids purchases of items.