Most Helpful Guy
You should phrase it as getting to know her better. For example, at the end of a conversation that you start, "I have to be somewhere soon, but you seem like a cool girl (and I like you), and I'd like to get to know you better. You free for a date sometime? (Maybe I could get your number)." And no offense, but this is a surprising question for someone your age, and I feel weird giving you advice.