Hello, I am new here, please go easy on me

I am in a JC now (neither good nor bad one) and there's this girl in my own class that I really like. It's so hard to tell whether she feels the same way for me or not. After the jc jae admission, we had some class outings and everyone in class exchanged msn and handphone number and etc. After I added her on msn, the very next day, she initiated a conversation with me and we just kept talking and talking, for about 6 hours I think.
From then on, we have always talked a lot on msn. Can talk for hours at a time, and we can just simply click so well and our msn conversations will never run out of topics even though we talk so much on msn. What's more, she's usually the one who initiates the msn conversation, cause I am more of the shy type who hardly initiates msn convos with girls.
However, here comes the problem. We can talk a lot via msn or sms, but in school, she just seems so indifferent to me. We hardly talk to each other 1 on 1 (i am usually too shy to) but I don't know about her. We only talk occasionally in school to each other, and even so, we don't talk that much unless we do group work together or something.
I don't know whether she likes me or not. We can talk so much via msn and stuff, but she just becomes so different when we see each other in school. On the contrary, she seems to talk more to other guys as compared to me. I don't know what she feels about me though, since we have gone out together alone to town, to libraries or Macs to mug, etc etc a few times. She also mentioned my name a couple of times in Friendster bulletins when she's doing some friend test like "Give the name of a guy" or something. Just the 2 of us, and yet we seem so distant in school.
Any help?

Why are we so distant in school?