How can I tell if a girl in my cl likes me?

There is a girl in one of my summer cles that I have become infatuated with but I am shy and horrible at flirting with/understanding women. So I would like some opinions as to whether she likes me or not as the summer semesters are short, and, even though we've only had a handful of cles, there are only two left. I know she has seen me sneaking glances her way (I just can't help it), but I have also caught her looking at me and whenever this happens she quickly looks away. I also noticed that when the professor funnily messed up a statement during a lecture, she glanced at me and smiled in a playful way that I, at least, would do to a friend across the room. It seems like she might like me, but she could just be friendly and like to look around during cl (I mean it is boring). So, what do you think, any input would be much appreciated. Thanks.