well, say

you "hey, im *insert name here*, whats up"
her "oh hi, im *insert name here* blah blah blah"
you "so what class do you have?"
her "*not important we all hate class*"
you" oh, well, im headed that way (complete lie) Ill walk with you"
her "alright"

start walking

say something about her books, binder, backpack, hey, you could even say, "I like your sleeves" make her laugh, Id love a guy who could make me laugh

continue conversation untill you get to her class, you could even become "walk buddies" (lame, I know)but who cares! at least youll be with her