This is totally lame...

Getting to know someone in a class atmosphere is fairly ideal, but some observations should be made. Like, is she always with a group of friends, or is she the loner type? Knowing something like this is a good springboard for your approach. Acting all nervous and shy with someone who is outgoing and around people, probably won't work most of the time.

Jam it back in, in the dark.

You might have just touched on the HUMAN weakness to not see beyond what lies on the outside. It's not something that only females project. If someone is not interested in something, it shows.

If you don't have a quality or anything that someone finds interesting, and you are a stranger to that person, what motivation do they have to give you the time of day, other than maybe a few minutes to humor you and keep their polite integrity?

It's a pretty sweeping statement, to call any girl (or guy) who balks at any nervous approach, a bitch (or bastard). You have to keep in mind that it's probably only you that has this mindset when walking up to and trying to start a conversation with someone you're attracted to. They are taking you at face value, and not thinking, "Oh, this person must like me, I should try and stay interested".

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