2. The ACT does not penalize incorrect answers. This means there is enormous shift in strategy required. The ACT actually makes things quite a bit easier in this regard. While on the SAT one must do a certain amount of mental gymnastics trying to figure out whether or not to leave a question blank or think about how many questions to leave blank in a section, the ACT requires none of these concerns. This affords you the ability to focus on nothing but the question at hand and the time on the clock. Simply answer each question to the best of your ability in the allotted amount of time and move on.
3. The ACT has easier questions but less time to complete them. This may seem trivial but can have some big implications depending on the type of test-taker you are. Some people are able to dissociate their emotions from their test and if they struggle with a question they have no problem forgetting it and moving on. Others, however, are streaky test takers. When confronted with a question or a series of difficult questions they may become frustrated and let their emotions hinder their ability. When confronted with a question that they are capable of but do not immediately understand, they may give up on the new question too soon. On the other this same personality can get on an emotional high after answering a series of questions with ease giving them the confidence to attack even very difficult problems and solving them with gusto. The crux of the issue is to determine whether your confidence levels are affected by your test taking and whether your confidence level affects your test taking ability. If it is the latter personality type that you into, then the ACT will likely be a better choice for you to make holding other factors constant.
4. A final important difference is that on the ACT, the writing section is optional. This is largely up to your own discretion. If you feel you are a good writer then take the writing portion and vice versa. It is important to keep this in mind when comparing the tests. If you feel you are truly a terrible writer and don’t want this to affect your standardized score as it inevitably would on the SAT, the ACT is a simple solution that does not hurt your application.
As you can see, there are many important issues that should influence your decision to take the SAT or ACT. Do not simply go along with what your friends and your school’s majority are doing. Analyze these differences and decide which test you are likely to perform better on. However, If time allows, taking both tests is still the optimal scenario.
Best ACT Prep Book: The Real ACT Prep Guide