You are enough

 Most of my best friends are 20 now, so I probably don't have many teenage girl followers. But some of this is still very applicable to girls my age and older. My favorites are #6 and #10.

 http://kateelizabethconner.com/ten-things-i-want-to-tell-teenage-girls/

"You were created for a purpose, exactly so.  You have innate value.  You are loved more than you could ever comprehend; it is mind-boggling how much you are adored.  There has never been, and there will never be another you.  Therefore, you have unique thoughts to offer the world.  They are only yours, and we all lose out if you are too fearful to share them.
You are beautiful.  You are valuable.  You are enough."

Also, completely another topic...I made this today (as chosen by Abby) and it turned out pretty well!