Re: Shows interest and attraction over text, but not in person ?
To be honest it sounds like she's just shy. I know before my more out-going escapades I've had the confidence to say things over text that I'd never say in person. Unfortunately this made it really awkward for me when I saw them in person, they were almost like "so where's the guy I was texting?" But then if you are also having the trouble in making conversation when you see her it sounds like you both suffer from this.
Do you ever see her outside of school? If not, make it happen. Go up to her in school one day, have your usual "hello" hug and what-not, then just pop it, "So we should go get coffee after school." or shopping or.. well, anything really. Maybe outside of the pressure of the social environment that school is you'll both loosen up and start talking like you do in text.
Why become someone else when you can become a natural?