Rural Area Student Initiative 

The ACT organization provides a free prep guide with an overview of the ACT, an official ACT practice exam, and a breakdown of ACT content. 

The Organic Chemistry Tutor (don't be fooled by the name!) has a 1 hour, 20 minute video that teaches you everything you need to know for the ACT math section. 

This article by The Critical Reader provides you with the most commonly-tested grammar rules, examples of them, and how to spot when they've been used incorrectly. 

This post by a student that scored a 36 details strategies to tackle each section, the resources they used, and tips and tricks they found helpful. 

The ACT Science section feels like it's in a league of its own. For only $9.64, For the Love of ACT Science breaks everything about it down in an easy-to-follow way. 

While we don't always love the explanations in the Official ACT Prep Guide, we do love the seven official practice exams the makers of the ACT provide in the book.