help me track my older kids internet usage

So i have a desktop that is in the living room, i dont mind it being used but i want to know what my kids are typing into it. The older girls use facebook which i think is stupid because your suppose to be 13 years old and there both under that. I see internet usage in the history but that doesnt tell me much. I lock the pc before work but the wife unlocks it and walks away. I want to disable facebook but my wife would freak out. So my questions is is there a safe keylogger i can use? My 12 years has created fake facebook profiles with pictures of tramppy looking kids as here self and its very not ok IMHO.

K9 Web Guardian by BlueCoat

alright thanks im going to check it out. I may force them to use this kiddie web browser i found recently.

No problem, I have used it on several machines before and it works great - especially for being free. Fully customizable for your blacklists / whitelists, allows you to enter an administrative password to access sites that would come up as 'restricted', has usage reports, etc. The people I know who use it have been very pleased with its performance.

It also works to use smoothwall for a firewall box. You can activate the web proxy server so all network traffic in and out is logged. You can also make it transparent to the end user or require a password to get to the net. I have busted my oldest son that way a few times and now he probably gets his porn elsewhere.