How to get closer with this girl

[Zyferous]

Okay, so there's this girl that I like, and we're kind of friends, but more of acquaintances
I've actually known her for a few years, but haven't really talked to her much at all, until recently.

She's a really spontaneous, bubbly, excited girl at times, but there are also times when she's really closed off and doesn't seem to want to talk to people. It's easy to tell in real life, but in indirect conversations such as over AIM, it is hard to tell which she is feeling, and so sometimes I tend to catch her when she is not in a mood to talk to anyone.

My problem is, I find it really hard to approach her, and I don't want to annoy her, or get on her bad side. She's also closed off in the sense that she has pretty much severed any networking sites such as facebook, twitter, etc. and is invisible 8 times out of 10 on AIM.

So far, in the past few weeks or so, I've attempted to talk to her more often, greet her in the hallways, hang out with her after class, etc. and have even casually attempted to ask her on "dates" (with a group of friends, of course) multiple times (denied on basis of grades however).

I'm receiving mixed feelings from her; sometimes we hit it off nicely and have a pleasant conversation, but sometimes, I feel like I'm trying too hard to make a conversation and it's pretty awkward. We tend to greet each other in the hallways, and we talk a few times a day, but nothing substantial; they're all just short conversations.

I really don't know where to go from here, the school year ends in about a month and I probably won't get much of an opportunity to see her until the next fall, so any kind of help would be appreciated.

If there are any other details that may be helpful, I have no problem with providing them, just tell me what you need

[sunnybunny8212]

since school is about to end, and you're worried you wont see her until next fall, how are you going to see her
during the summer?

to me it sounds like she may be going through somethings on her own or at home... or shes shy.
if you guys hit it off well a couple of times, don't worry about getting on her bad side...
maybe you should ask her if something is wrong on her part, and ask her what up?
address her on that subject if you're curious to know why she seems to be quiet and away...
and in a way, if you're always there to comfort her, [even when she doesn't ask]
she'll lean closer to you maybe..

hm, i hope that somewhat helps... its just a thought :]