Here are the key tests. The SAT I and ACT . The answer probably depends on what's required by colleges you hope to attend. Some accept either test. To make sure you know which tests are required, check the catalog of each college.
Students often take it as sophomores and again as juniors.
It gives you another chance to show your English skills. If you think this test might help you, talk to your counselor. The SAT II . Each SAT II exam covers one subject such as chemistry or world history. Competitive colleges may require writing and math tests and ask you to choose a third test.