I was coming out of a class and I saw a girl I had spoken to once in my class. She was maybe 10 feet away when I saw her walking towards me, i looked at her and smiled, she smiled back and waved her hand, I said hi, she said hi back, but she did not stop walking, so I did not stop walking either so we walked past each other. (All this happened within 2 seconds)

I keep running the scene in my head and cannot come up with anything else I could have done that would not bring my value down. should I have stopped? walked backwards? any ideas?

You didn't do anything wrong, really. I'm sure you'll see her again, and if you have something more to say, say it. At least you said hi, showing that you arn't afraid of her or something. I'm sure she doesn't think you're a dick just because you didn't stop and engage her in a conversation.

Nothing wrong with what you did - you've established familiarity with her. However, it's important that you act before you fade and just become another face in the crowd. Next time you see her, just stop in front of her and say hey. She'll stop and you can open with pretty much anything. In cases like this, I usually chat for a minute or two and then introduce myself and find out her name, which is a pretty good lead-in to get her number and set up a time to meet later.

thanks for the advice rigoberto, i will try what you said next time I cross a girl I know.

These guys are wrong, what you did was chicken SHIT.

I mean, at least it wasn't the worse case of scenarios, but still...

You should have stopped her and said,

"Wait a second... I know you from somewhere, don't I? Wait, let me guess. You work at [some strip club] right? (SMILE). Wait, that's not it is it.... OH! You were the one flirting with me at the massage parlor, you have the worse hands EVER!!! (laugh). Nah, wait, now I know you are... you are that quiet girl that no one ever talks to in our class. Why don't people talk to you? You don't seem that weird..."

Nobody's saying that he couldn't have opened her right there and then. The point is that no harm has been done - they know each other now, and the next time he sees her, he'll be in just as good a place (if not a better one) to open. My point is that he needs to act quickly though.

ya next time stop for sure