How can I get closer to a girl at this rate?

[Zane Kapalo]

I guess I should start off with the whole story. I'm in High School, and there is this girl in my class that I really like, but I feel like I've been failing this whole time. I know I have. All I have been able to do is stare at her, and I know that is something I seriously shouldn't do since I feel like she's been avoiding me this whole time. I don't know how to feel. In gym, she looks in my direction and goes where I'm not at, but in class, she doesn't mind coming near me. I think she talks about me to her friends since they always look in my direction as well. I am really confused since they look in my direction and smile, and I have no clue what to think.

Some things I've done that I feel are mistakes are:
-Kept on staring at her. (Fixed that recently, but I feel as if there is a lot of damage from that.)
-Tried adding her on Facebook before even talking to her in person. (I'm an idiot when it comes to having a social life)
-Speaking of which, I'm pretty quiet in class and only get active when I'm with my friends..
- I get nervous around her and fiddle with my stuff.
-I know I said I fixed the staring part, but I always end up looking in her direction, even if I see her at the corner of my eye.
-I'm too shy and nervous to talk to her or have a real conversation.
-I probably made myself look stupid.

Some good things are that today in class she asked if anyone had candy, and I gave her some, and she seemed to be happier around me, and she would smile while she looked at me when I was speaking. (That was before the whole staring thing. Now I find that I shouldn't even bother getting near her to speak to people.)

There are so many more issues that I have that I can't even think of right now, so I think a whole Girlfriend 101 tip book is what I need right now -_-. Please give me as many facts and details as possible, thanks.
I also have no idea what so ever on how to approach or talk to girls.

[Scotty]

Just be social. Some people are naturally introverted. If you like a girl talk to her and get to know her. It doesn't have to be in a large group or anything.