Do girls ever act aloof to a guy they like? I know it sounds dumb but hear me out?

I know it sounds like a no right off the bat, but there is a girl I like in my 6th period. She is quiet except around her friends, but everyone says she is really nice. I sometimes notice her looking at me, but I'm not sure if she likes me or not. When she looks at me it's not disdain, her face is just blank. But at the same time, I can sorta tell it's not a passing glance. She hardly ever talks to me unless I initiate the convo., which I've only done once because I'm afraid to say something stupid to her, and it lasted like a couple of seconds. Other than that, she sits in the back and just watches the classroom. Anyway I can start a convo. without being random? Good Topic? Thanks.