Well, I was just notified the day before testing because CST week started off with 5th period which was biology for me.. so I had only one day to review like everything. I needed more than one day to get all my stuff together

But yeah, CST = California Star Test or something like that..
I just want to get into a good college, lol, so I need this AP class and I want to save as much money as possible
CST = California Standards Test
Anyway, I'm sorry to say this but.. people don't usually study at all for the CST's
I went into it every year without knowing what I was taking o_o
But yeah, take advantage of summer & if you really want to take AP Biology, take some biology books and study on your own

It should help.