As a private SAT and ACT tutor since 2006, I know I need to keep on top of the best test prep materials. I got my hands on the 2020 Official SAT Study Guide and below are my thoughts.
TLDR: The 2020 edition of the Official SAT Study Guide is nearly identical to the previous version, and inherits all the same flaws and virtues. The only things changed are the tests; Tests 2 and 4 have been replaced by tests 10 (Oct 2018) and 9 (Oct 2017), and the order of the tests is now 10, 9, 8, 7, 6, 5, 3, 1. It is still a convenient way to get hundreds of the best practice questions available anywhere, and still a source of extremely mediocre explanations.
The SAT Official Study Guide has always been the best single book for SAT and PSAT preparation. It has authentic questions taken from actual SATs, and therefore provides much better practice than any 3rd party offerings. 6 of these tests can be printed out for free (minus printing costs!) on the College Board website, but the first two tests (those labelled 10 and 9) are currently not. I expect those two will soon be added to the website.
So, you don’t need this book. Why would I call it the best single book for SAT/PSAT preparation? Because it is a convenient source of the most realistic practice questions you will find. Unless you have access to very cheap or free printing, the cost difference is negligible and the hassle difference can be large.
I have compared this book and the previous edition side by side; everything is identical, word for word, until you get to the practice tests right before page 300. Practice tests 2 and 4 have been removed, and two new tests have been added. Test 10 is the test that was administered in October of 2018 and test 9 is the test that was administered October 2017. The new order of the tests descends from 10 to 1, skipping the now removed tests 2 and 4. The explanations for questions in tests 10 and 9 are a bit longer than the explanations in tests 2 and 4, so the entire book is now 1310 pages instead of the previous 1275 pages. These explanations are not noticeably more helpful, however. Since the College Board makes both the SAT and this study guide, they have a vested interest in explanations that avoid mentioning the tricks and patterns of the SAT. This means that a large percentage of their explanations are unhelpful, or at best, suboptimal.
Beyond the practice tests, the book does have some value. There are discussions of the test length and structure, and some discussion of the concepts tested in the SAT. There are also a couple of chapters on the essay that are useful. While the SAT essay is a failed experiment that remains only because some schools haven’t yet come to accept its failure, many students, especially those applying to UC schools, will still want to take it. This book provides information about the essay, it’s structure, scoring system, and includes some helpful examples of essays that received different scores.
The best way to use this book is to take the sections from the test as practice. Start by taking sections untimed, and as you improve, take sections timed, and finally, start taking entire tests timed. After each section or test you have completed, you will want to mark every question you missed and review every mistake you made. Try to correct your mistake without seeing the correct answer in front of you. Take notes on your mistakes, and make sure they are clear and organized enough that you can go back and review these notes later. Your notes should include what you did wrong and what you should have done instead. After some time, you should retake every question you missed, without notes or help in front of you. This is how the students who make large SAT gains practice.
This book is not the end-all be-all of SAT prep, but it has hundreds of the best practice questions you need to improve. The explanations and strategies leave much to be desired, but those are what Youtube, Reddit, and private tutors are for.