I have a crush on my lecturer, help?

I'm on a postgraduate course and have a huge crush on one of the lecturers, he's about 40 and I'm 26. I know lecturers probably can't date their students but would this still be the case for mature students on a postgraduate course? Could someone his age be interested in someone my age? What kind of signs should I look for that he could be into me, he does look at me but he does have to look at all his students I guess. I don't want to be too obvious in case I embarrass myself but how can I show I'm interested? I cannot stop thinking about him! He's not married but he could be with someone and I just don't know about it.
I have a crush on my lecturer, help?
Post Opinion