My friend, what you are attempting is known as a ladder jump.  Read all about it at 
http://www.intellectualwhores.com/masterladder.html  You may already be an Intellectual Whore, but at least you seem to know it.  It took me many years to see that in me.
Please note that I am not the webmaster, nor the guy who wrote that, or in any way affiliated with the whole thing.
Back to the issue at hand- you need to tell her one simple thing: "Baby, I want to ride you like Silver, bucking and snorting into the sunset!!"  Wait, no, don't do that.  What I meant to write was "The feelings I have for you are more than friends-feelings, and I want to be your boy(TOY)friend.  I think you have similar feelings too.  We should give a good, honest shot.  If it doesn't take, we can go back to being friends."  Somebody here please rewrite that for me so it doesn't sound so robotic.  Can you tell I have had less girlfriends than fingers on my left hand?
And just in your secretest of hearts ElPresidente, that part about going back to friends is most likely bullshit.  Keep that to yourself.  It is worth it to go for it. Some smart ass wrote that cowards die a thousand deaths, and I didn't think it was true until it happened to me over and over, chances that I never took killing me again and again.  You're young, you'll meet plenty of people in your life.  Don't let a chance for extreme joy pass you by in favor of stunted happiness.