Let me guess: you are said female student?
If your instructor is wise, he does not show it at all and tries hard to keep a professional demeanor at all times. It's bad form for a college instructor to have any relation with any student, other than a "professional" one. Bad things come from it. Mostly for the instructor.
My guess is he's acting like any other person with a like for another and struggling not to be overly nice and chatty to you, as well as "looking" for you all the time. Be it in class or in the corridors while passing by.
Or he seems to remain at a distance but subliminally you feel there's something going on. It all depends on the level of overtness of earlier mentioned behaviouristics.
Now, if you're not said student, and your name correctly implies that you're a women AND you are said college instructor instead... the same applies. Above behaviour is probably yours and above advice on how to act applies double time.
There's no way you're going to convince us that this is merely a hypothetical question. In matters such as these, "hypothetical" is never an applicable term.
Don't pursue anything as long as the student is a student in the college of the instructor. It's also a no-no if student and instructor are in different colleges. Except when there's little to no age difference, then it's just two consenting adults in different occupations, so to say, if you ask me.
It may seems safe to pursue something if you're not actually taking classes/giving classes with/to said instructor/student, but chances are great that it's going to be found out and then it's hell to pay for the instructor as the student will most usually always be seen from a subordinate/weaker position that the instructor took advantage of.
Things are different if you're a post-grad/Ph.D.-student. Which usually means you're on a salary and have an assistant professorship possibly. Then it'd be dating a co-worker. I've seen that happening a lot and there's no problem with that other than the regular objections against co-worker relationships. Also not advisable, in other words, but purely for practical considerations.
Do yourself a big favour and don't go this route. And please provide some more info than this. Now you've gotten us interested after all.