Most Students Take the Exam(s) in the Spring
Most high schools will take their Junior class through the ACT or SAT test as a group in the spring, typically March or April. This is the generally accepted time frame that can accurately judge the student's knowledge of the subjects covered on the tests.
If your high school does not schedule the tests for you, then you can go directly to either visit the ACT Website or browse to the College Board website (for the SAT) and register for either exam yourself.
Taking the ACT or SAT Multiple Times
You may want to take the ACT or SAT two or sometimes even three times. Don’t laugh, this is actually very common as students try to get the highest possible score. If you choose to take either the ACT or SAT more than once, try to schedule the second test before the summer between your Junior and Senior years in high school. The administering authorities for the ACT and SAT reduce the testing locations during the summer and finding convenient testing sites can be difficult.