If you know a teenager that is about to go on a killing spree, you should first recommend to them this free on-line training video:
http://www.i-am-bored.com/bored_link.cfm?link_id=13271 The game is in early development, but has come a long ways from the original version. It is a family wholesome killing game, as all the victims are young males. You have a limited timeframe to kill, and limited weapons and bullets, so it is slightly more realistic than the store bought video games. However, nobody gets to shoot at you and you can't move around, and all the people are in 2-D across the same line of fire. But it is a great tool to train kids on how to shoot people with guns, especially if your goal is to just shoot them in the knee. David Locklear