Many parents come to a crossroads regarding which admissions test would be best for their child. Many stick with the test that is more prevalent among colleges in their area. For example, the ACT is more prevalent in Oklahoma and Arkansas, whereas the SAT is more popular in Texas. Surprisingly, this is not because colleges in these places exclusively require one test or the other. In fact, I do not know of a single school in any of these three states that exclusively requires either test. Therefore, students should choose according to what is best for them.
The best approach for nearly every student is to take both tests. A student may elect not to send the scores to schools from any test until he or she is ready. For example, say a student plans to take both tests during the spring of their junior year but is not sure how they will do. They can decide not to send the scores to any colleges until they find out how they did. There is an additional fee but it might be worth it just to relieve some of the pressure. If they like their, scores they can go ahead and have them sent to the colleges to which they are applying or they can decide to take either test again and then send the scores.
Another reason to take both is that some students may do better on one test than the other. This may depend on a student having skills that are better suited to one test more than the other. For example, students who know all the key math formulas have an edge on the ACT because these useful formulas are not included in the test instructions; students must know them. In contrast, these formulas are present as part of the SAT instructions so students do not have to know or memorize them.
Sometimes a student may feel more comfortable with the nature and design of one test over the other. I had a student last year who did well on the ACT math section but poorly on the SAT math section. This difference appeared consistently on both real and practice tests. She was above the 60th percentile on the ACT math section and around the 40th percentile on the SAT math section. The only explanation I could come up with was that the layout of the ACT fit her better. Taking both tests will give the student feedback that he or she can use to decide if another test is a good idea and which test on which to focus their preparation. If the student does considerably better on one test, they should probably study for and take that test again.
Excerpt from The Parent’s Guide to the SAT and ACT by James Pipkin, 2007