The Scholastic Aptitude Test, SAT, has three subject areas: writing, critical reading and math. The writing portion consists of multiple-choice questions that test grammar and also requires writing a short essay. The critical reading portion tests reading comprehension and ability to complete a sentence. The math section asks questions related to geometry, algebra and statistics. The ACT has English, math, reading and science sections, with an optional writing test. Each section is multiple-choice with the exception of the writing test, which requires students to compose an essay.
It is common to think of the ACT and SAT as tests of intelligence, but these tests are designed to measure a person's knowledge. Though intelligence is a factor in terms of the manner in which people learn, the ACT and SAT are knowledge-based tests that help colleges determine how much one student has learned in relation to another student. Because applicants are often from different high schools with varying curriculum and academic difficulty, the ACT and SAT help to level the playing field for purposes of objective comparison among students.
For many colleges, SAT and ACT scores are used in conjunction with a number of other factors, such as high school class ranking, evaluation of academic coursework, improvement in grades between the first two years of high school and the final two years, letters of recommendation and a personal essay. Most colleges will not reveal a minimum score threshold for admission, but Harvard University lists a range of scores on the SAT Reasoning and Subject Tests achieved by admitted students.
More than 800 colleges and universities have adopted a modified ACT and SAT submission guideline that gives applicants several options. Some of these institutions only use the test scores for placement or academic advising. Others require scores exclusively for out-of-state applicants or when a minimum GPA and class rank is not met, and some give the applicant the option of not submitting the test scores at all. The admission pool for a number of these schools has become more diversified as a result of these changes.