So here's a brief run-down of stuff I've seen.
Chatroulette.com: Students love to use this feature - it shoots them to random people all over the world. As an adult - I think it's totally creepy. You can not only see the other people but you can talk if you both have audio capabilities. There's a pretty high ratio of pervs on this site. Unless of course you're into naked Gustav. Omegle.com is a similar site but without the video capability
I-chat - Great for internal school communication when you're supposed to be studying. Smilies optional.
Skype: Skype is the new tool for phone sex (though I've only heard them talk about it - I sure hope it's not happening at school) . Sorry - but there's even a name for it "Skype-urbation."
Facebook: All the kids can totally get around any block, and if they can't, it's just a matter of seconds before they find someone who can. Facebook is like the social gossip center. Stories told, photos shared. Most teenagers have no privacy blocks on their Facebook pages.
Creeping: See Facebook - without privacy blocks it's pretty easy to creep on someone else's page, check out the hot girl who your boyfriend is flirting with or his ex. This is the correct term.
Trolling: You're a troll if you only have negative comments to make and do it for fun.
Twitter: Pretty much the same as Facebook
Other Favorite Teenage Sites:
You Tube - Viral videos get spread quickly between teenagers
Memebase.com - Funny stuff
Iwastesomuchtime.com - Funny stuff
So, anyone have anything to add to this list? As a writer, with things changing so quick via technology, the old adage of be sort of glossy with it (as in, mention it, but brush over names or specifics) is wise. It's hard to keep up when you're an adult with loads to do besides be on Iwastesomuchtime.com!