Why, in class, does she keep looking at me but never talks to me?

im a freshmen in highschool. well in class, we sit a couple desks apart but we can see each other if we look. so I kinda like this girl but I don’t know if she likes me. in all the classes we have together, whenever something funny or wierd happens in class we automatically look at each other and share our expressions but we usually laugh or make faces, but not really talking. we look at each other I bet at least 10 times each class I have with her. some times we poke fun at each other in class and laugh during class. then after class its like she never notices me. she also kindve pretends she hates like on a friendly level so whenever we barely talk, its about some stupid question one of us asked in class or something stupid we did that we poke fun at each other about. but we never really talk like in a real conversation. sometimes we do but we usually dont. I swear she likes me in class, I mean thats why she keeps looking over my way to she what my expression is about something right? or is that just something girls do? then I never talk to her out of class. should I try just talking with her outside of class? I mean were friends but not like super good friends. I dont want to risk our sortve friendship for thinking she likes me when she doesnt. I mean I think im pretty good looking, I play sports, I’ve had a girlfriend before. its not like im some nerdy kid or something. help me out with some advice on what you think shes thinking or what I should do? thxx