This is nicely descriptive and very well written (except all the "Zabrina"s slow the flow a little). Also, there's no real hook. Nothing makes me say "I've got to keep up with this story".

This is a good opening :) You set the scene very well, and your boarding school seems realistic. I like your writing style and how we get quite a lot of Zabrina's emotions and excitement through, but some more proof-reading would really help - for example, there are several times where "she" would be better than "Zabrina", you switch between tenses occasionally, and there are a few more grammar errors (e.g. "girl's dormitory" should be "girls' dormitory".)

[The girl with ginger curls pulled down her bed sheets to look at the mysterious black haired beauty.] - I also feel this line doesn't quite work. You use the same point to describe both girls, and the description seems underdeveloped.

But otherwise, a great beginning! You describe the music brilliantly, and Zabrina's reaction to it is very well written :)