Teacher acts inappropriate?

My anatomy teacher's relationship with some of the guy classmates are quite questionable. I'm not saying that she's doing anything with them though! But that she's not exactly acting like a teacher towards guys... 

A senior started flirting with her so that the project we had in class could be prolonged by 3 weeks and it worked. Also another student (senior, male) came in class one time and he was talking to her about something and suddenly he lifted his shirt up to show his tattoo to her, and she started getting a bit too touchy on his chest... I get that the tattoo was cool, but he's a student, and I felt like it wasn't right to touch a student that way, even if it wasn't meant to be sexual. 

Another time a student asked if she had an Instagram and she told me "I post inappropriate things on there, but you can follow me once you're no longer a student here." She's just very chill and way tooooo close to male students, and even treats them better. Like if a guy and girl were both being disruptive in class, the guy would get a warning but the girl would be in serious trouble. My boyfriend is constantly on his phone in that class, and he never gets in trouble. I used my phone after finishing my work (we're allowed to) and I got yelled at in front of the whole class. 

I don't know, maybe I'm over exaggerating at some of this stuff, but I just don't think it's appropriate for a teacher to be doing this. I see it as weird if the teacher was a man and acting like that towards female students, but bc it's not I feel like if I were to talk to an administrator then it wouldn't be taken seriously.