SOLVED. YA fiction publish in the 2000's at least. About a girl who goes to a isolated school on an island where strange things are happening to the students. [s]

[Cassandra]

So I remember a lot about this book. Idk if this is spoilers but this book was a about a girl who I think was named sarah and she went to the very isolated private school like absolutely no contact with outside world. She joins a club/cult that drinks a chemicals that I think is called brocynme(bro-co-mean). And I remember this one dude who I think was named zack who wanted to escape from the school because he suspects the school for experimenting on students to make them perfect before they send graduates home.

[Kris]

The Assassin Game by Kirsty McKay? There are different cover images.

Google search - site:www.goodreads.com "young adult" mystery "private school" island "drink"

[Cassandra]

No it wasn't about a killer cult the whole school was being brainwashed by the faculty and it ended with a cliff hanger

[Morwenna]

Maybe Sanctuary Bay?

https://www.goodreads.com/book/show/2...

[Cassandra]

Yes!