Book advices to improve CR score in a short period of time

<p>"The Best American Essays of the Century"
I heard that this book has a lot of similar essays as CR.
Im considering reading it and analyzing it meanwhile(like find author's purpose, summarize the paragraphs).
Im running out of time,, test is Oct and I was on a nearly 600 level. I want 680 guys!
What do you guys think about it?
Anyone wants to work together so we can discuss about the essays we read?</p>