How do I find out if this really shy girl likes me?

I really like her, but she is really quiet and I can never muster up the confidence to ask her. We talk, but really only about school. Speaking of which, she is in a few of my cles, and sometimes I see her looking at me but I'm not sure if I am just overestimating the situation. I have never really asked anybody, so I don't really know what to do. Also, I fear that if I ask her she will say "yes" even if she doesn't like me since she is one of the nicest people I know. Also, are there any indirect effective ways that will help me find out. Please help!!