While many students get away with putting math formulas into their calculators, and many businesses market programs that enable students to download the math formulas that students need for the test, storing information on your calculator is prohibited on the ACT.
With the test cheating scandals in recent years, the ACT is really cracking down on security procedures. This test will lose its credibility if cheating is widespread, so the ACT is doing everything they can to stop it. Instead of looking around for a way to put formulas into your calculator, have no worries by spending a few minutes memorizing what you need for test day.