The writing exam is optional. You should take this test if any of the colleges you are considering requires the test. You should also consider taking the optional writing exam if you are a good writer. Scoring well on the Writing Test is one way to help yourself stand out to colleges. Few students voluntarily take this exam, so your choice to take it shows initiative and highlights the fact that you are willing to go beyond the minimum requirements. This is a highly sought after quality in a student and the ability to communicate well through written English is also a highly sought after skill.