The ACT English System: A step-by-step, first-things-first, systematized, secret-free, no gimmicks, no tricks, no wasted time guide to the ACT English test (The ACT System)

A lot of these kinds of books claim that they will help, and this one really does. Good, straight forward grammar rules and advice. This book will give you the greatest boost in the least amount of time. If you are in the 26-28 range and want to move up into the 30's, I think this is the right book. If you are in the high 30's and trying to get a 36, you will need a more intensive book. My advice is to get this book when you first start studying. Then decide if you need to move on to a more comprehensive and time consuming book.

What I like most about this book is that the most important or asked about material is taught at the front of the book, then constantly reinforced as new lessons are introduced. I definitely recommend this book to anyone looking to improve their ACT English score!