Why former teacher did not accept my friend request at facebook, but accepts requests from my schoolmates?

Because facebook does not matter. A freind request can be skipped by accident.

You can add me if you want. Get your friends to add me too. I am a year 3 student from Ngee Ann Poly. My details is below. Anyway a short story: I am a quiet girl who looks childish but is actually mature beyond her years. I dont like comics or manga. I neverr pick up a jokes book to read not that i am someone without a sense of humour. I am actually really very easily amused, i just prefer my serious self. To people i like, i joke and smile alot and as for people i feel intimidated by or dislike because they probably hate me, i either withdraw into myself or give nervous smiles and titters. My first instinct in any scenario is to protect myself. So i have to feel very secure that someone likes me, before i open up.For the most case, yep i probably never do. People think i am crazy over dogs and they are probably the only things in the world i care about. What they dont know is i am rather caring as an individual. but i dont care as in like... but i wish everyone well and i dont hate anyone even though how much they have wronged me before. I just feel anger but that fades after a while. I am not crazy over dogs. I just prefer being around them cause they are non-judgmental. But as long as a being has feelings and can feel hurt, in my eyes, they are all the same. I would never hurt them unless anger clouds my judgment for a while. I am pretty idealistic and i dream of a world where everyone are friends and happy. Well, i know. Maybe thats why i am sad cause the world is not so nice.

did you tell her that you were one of her students ?

well, teachers arent actually aloud to add students to social networking sites so adding your class mates can make her/him loose there job, but why adding them but not you, i dont know... was you annoying/mean to him/her in class?