Bro, whether you are perceived as the creepy kid coming up to you randomly or the super cool dude that seems really interesting is entirely in your attitude and body language.
Don't walk up and act like a little *****. Be a man, picture that girl sitting there masturbating to your image with a vibrator. Picture her body shaking all the **** over her bed and she can't stop. That's cause of you.
I don't give a tit**** about whether or not there is a proper opener. I walk up to the stranger say, What's your name with a big smile on my face and a relaxed aura around me. Or I say, hey my name is Ryan and offer my hand. That's simple and you don't need a ****ing opener.
Me: Hi, I'm Ryan!
HB: Oh, why uh, hello!
Me: You know, I've seen you but I don't know your name and I know almost everyone at this school so I couldn't forget about you. ( or perhaps you're too pretty to pass up.)
Probably will blush shyly. Then just start a conversation.
Or be like:
Hey you, what's your name?
Uh, hi im samantha.
I just wanted to say you have the coolest necklace/earrings/ bracelet. ( Is that turquoise in your earring? Turqouise is the ****)
JUST DO IT. Then be light hearted and try to make her laugh. Don't think too hard, or think at all. Just walk up as the guy that she should know.
If she's a *****, **** her and go talk to another girl. Girl's love to talk and you can get them yapping with the simplest question.
But if you want to use an opener, which is reccomended, LOOK AROUND. Opener's are EVERYWHERE. I repeat EVERYWHERE. EVERYTHING IS AN OPENER.
"See her hurrying? My your walking fast, you late for class? You know it's naughty to be tardy."
Weather's been freaking weird?
"It's ****ing winter and the sun is still shining and it's 80 degrees out, can you believe this ****?"
See her carrying an economics book?
" You taking economics? ****, I hated that teacher. Or that class was the death of me." (HS students unless they are antisocial nerds will always sympathize with someone talking crap about education.)
Remember:
OPENERS ARE EVERYWHERE.
Plus situational openers are always better cause they flow more with the environment and the mindframe of the girl.