How to be friends with a Unknown girl in my class?

[pratik]

I know this task is not so complicated but it is for me......
I am a teenager studying First year in senior college and I am new in my college, don't have much friends. And after attending certain lectures in my college I have found that there's a girl keeps looking me. And i'm sure she is looking at me.,

And still she was looking whenever she had chance. Many times I caught her while looking at me and then she take her eyes away.... She kept looking me for 5-6 days. We have never talked to each other, And also we don't know each other. But she is smart and modern, and maybe shy. She is a very nice, She appears to be a very interesting person, I really want to know her closely, She is rich and her cousins and brothers are very powerful personality ....

after this suddenly she stopped looking at me, i thought if she keeps looking i will cross look her.
But no!! she stopped looking at me. My opportunity of being friend with her is gone??....i don't know what happened... And I can't stop thinking about her, and now I keep on watching her during lectures but she can't notice that I'm watching her.
(because she sits at first or second bench and Me sit to next row from her on third or fourth bench)

And from last 2 years I've never talked to any girl in my class or college, so it is hard for me to directly talk her, I always try to talk to her but I'm in extreme lack of confidence.

I can't approach directly to her because she is always engaged with her class friends. She is never alone. If she is alone she put on her phone.....

This is being ultimately hard for me. I have also tried facebook, sent her friend request but no response, messaged her but no reply..
tell me friends if there is another way to be friends with her.
If she was interested in me then why she stopped it,
what maybe she thinks about me?

Please friends help me out on this. And please don't make fun of me or this problem..,
Serious answers are needed.
Additional Details
It would be great if Indian people Answers this question....
Thanks friends for quick answers......
But asking her among all can make her embrace? or feel odd?
I have to find out right timing for this.