The best way to study for the ACT is to have a test prep book guide you through the material, take practice tests, and repeat. My favorite ACT book out there is the Real ACT Prep Guide, which is the only book with real ACT questions. The Princeton Review one might be worth a shot, and don’t bother paying money for the SparkNotes version because it’s available online at www.sparknotes.com.

I think if you don’t need a big improvement and you’re very motivated, then you can buy books and just practice a lot. I needed to make a big jump on my ACT and went up in every section with the course I used. I used an online course at prepme.com and I think my parents paid $500 for it. It was cheaper than a classroom course and I had a tutor from the university of chicago so it worked well. The tutor answered all of my questions and kept me motivated and sent me weekly update emails. My parents read about it in business week as some top entrpreneur contest thinghy so that’s how I found out.

Good luck! Make sure you practice and study hard.