Albert Einstein, who's generally considered a pretty smart guy, said, "It's not that I'm so smart. It's just that I stay with problems longer." That type of commitment, as anyone who's studying for the ACT knows, is its own form of intelligence, and it's what will help you accomplish your long-term goals.
This book guide is meant for students looking to "stay with problems longer" and study intensively, like 100 or more hours, to maximize their scores on the ACT. If you're a student who wants to leave no stone unturned as you prep for the ACT, then these are the books for you.
Before delving into the ACT prep book list, a word about what perspective I'm coming from in my recommendations.