Resource Review: The Official Guides

I know how tough it can be to decide what books to buy to prepare for the GMAT. Even tougher, if you go to the bookstore and come home with an armful of them, where do you start? In this, as well as upcoming resource reviews, I'll help steer you through the maze of useful (and not so useful) GMAT resources.

Many students disregard The Official Guide for GMAT Review because, well, it's "official." It doesn't give a lot of hints and it certainly doesn't divulge "shortcuts"–if you asked the authors of the test, they'd probably tell you that it isn't about shortcuts, at least not of the sort you learn in a Kaplan or Princeton Review course. Despite all that, The Official Guide (and two other supplemental books) are the single best resource you have in preparing for the GMAT.

The Official Guide for GMAT Review

Weighing in with over 800 pages, 800 practice questions and answers, and a bright orange cover, this book is the best twenty-two bucks you'll spend on the test, hands down. When you're in the market for practice questions, your number one priority is authenticity. Since the Official Guide is written by the same folks who write the test itself, it doesn't get any better than this.

There are some drawbacks. The section overviews are well-nigh worthless, and the explanations are often opaque. You'll never find the "faster way" in this book, but if you're working with a tutor, that's what he or she is for. The book claims that questions are organized by difficulty level, but there are no markers to indicate what those difficulty levels are; also, I suspect they are organized only in the most general manner.

Most students will start with the Diagnostic Test (section 3), which is actually one of the more challenging parts of the book. The questions, on average, are set at about the level of a 600-650 test taker. Because the diagnostic is not adaptive, your score (the book provides a conversion table) is not all that predictive of how you'd do on the computer-based GMAT.

In other words, this book is far from being the perfect GMAT resource, but because it is the one location where you'll find hundreds of authentic test questions, it's a must have. It should be at the center of your preparation from day one.

The Official Guide for GMAT Quantitative Review

More of the same. This book is slimmer (only about 300), cheaper, and green, but if you need more math practice, it's a great resource. One caveat: the average difficulty level of questions in this book is somewhat lower than that of the questions in the Official Guide. If you're already getting a 650 or better on practice tests, or if you are comfortable with the vast majority of math problems in the Official Guide, go ahead and skip this one. If you're not yet at that level, this is an excellent supplement to the orange book.

The Quant Review book does have more actual math "review" material, but again, it's very official in nature. Buy it for the questions; read the review if you're stuck in the subway without a pencil and scratch paper.

The Official Guide for GMAT Verbal Review

As you've probably guessed, this is the verbal equivalent of the above. If you're keeping score at home, it's purple. There isn't the same difficulty-level difference between the Review book and the Official Guide for verbal questions, so I can recommend this to just about anybody.

Further, the difference between authentic questions and inauthentic ones (i.e., those generated by writers at test-prep companies) is much greater in verbal material than in math. I should know: I've written hundreds of practice verbal questions, and matching the voice, structure, and objectives of the original is a daunting task. Some inauthentic practice materials are better than others (more on that in future tips), but you should take advantage of all the "real" questions that the testmaker has made available.

Over the next few weeks, I'll write about some of the better resources published by test-prep companies. Much of the GMAT shelf at your local bookstore is useless and redundant, but I'll direct you to the gems that will help you efficiently raise your score.

About the author: Jeff Sackmann has written many GMAT preparation books, including the popular Total GMAT Math, Total GMAT Verbal, and GMAT 111. He has also created explanations for problems in The Official Guide, as well as 1,800 practice GMAT math questions.

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