I don't think this will help you, but here's how I successfully asked a girl to the prom recently:
We were on a school trip and she was sitting a few tables down with one of her friends. After building up my courage (with the help of the people sitting at my table) I simply walked over and stammered out "Would you like to go to the prom with me?" at first she wasn't sure but her friend quickly convinced her to go. And now I have a date for my senior prom, which is also the first time I'm going on anything even resembling a date.
I suppose I might of taken a gamble asking her right in front of one of her friends, but this particular friend never had a problem with me (not that many people do) and has a boyfriend and thereforth, no reason to be jealous.
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The improbable goal: Fear nothing, hate nothing, and let nothing anger you.