How should I deal with an annoying coworker who has a crush on me?

So there's this16 year old girl working at my job for the summer, and its obvious to everyone in the office that she has a silly crush on me but she shows it in the most aggravating ways. She's sassy, annoying and downright rude to me but is an angel with everyone else. Naturally, people don't seem to understand how much she gets on my nerves, "oh she just has a crush on you." Its as if she wants to get a rise out of me. Thing is, she's the daughter of my boss's good friend. Is there any way I can give her a piece of my mind in a way that won't risk me getting fired, or better yet how can I get her to just leave me alone???