ACT Test
The ACT Test is an alternative to the SAT test: most colleges require you to submit your choice of the SAT or ACT when applying.
The ACT covers English, Math, Reading, and Science Reasoning. The four sections are scored from 1 to 36, and these scores are averaged together to yield a composite score that also ranges from 1 to 36. The test also includes an optional Writing (essay) portion, which is required by some colleges. To make sure you don't shut down any college options, it's safest to take the optional Writing test. However, you can make an informed decision by researching various colleges' policies here.
To many students, the ACT may feel more straightforward and familiar than the SAT. For example, the ACT tends to avoid obscure vocabulary and brainteasers in favor of everyday vocabulary and core math concepts.
While the ACT may sound easier, remember that both the SAT and the ACT are scored on a curve. As a result, students should ideally experiment with both tests to discover which is a better fit for them.
To prepare, check out the test maker's prep materials or prep books such as The Real ACT Prep Guide
For more information about the ACT, visit ACTstudent.org.