<human>: Could you distill the essence of the text into 1-3 sentences?

English isn't my native language so I really apologize for any grammar or logical mistakes. I really like this girl from my school and would really really like to ask her out but there are a few problems which stop me from doing so. 

Firstly I'm absolutely certain that she doesn't know me nor we have any common friends. Second even though she is a year younger than me she is a bit taller. Third since we have move from classroom to classroom during breaks that my only small time window to talk to her or even see her.

Number two isn't that much of a problem but I really have no idea what to do to strike up a conversation with her so that she knows I exist. Normally I am a quite straightforward person but unsure if showing that I am interesting in her at first is gonna make her reject me. Since she doesn't know me I'd like to befriend her first just so we get to know each other better. I neither have her Facebook, any friends who can introduce me to her nor know any of her friends.
<bot>: I'm head over heels for this girl but she doesn't know I exist. No idea how to become her friend.