This was formerly know as the Achievement Tests and was renamed the SAT II: Subject Tests. They are administered by the College Board and widely used as a college entrance exam. Students may take the test more than once, but only the highest score is reported at the year of graduation.
See Scholastic Assessment Test II.
One-hour tests measuring knowledge and ability that apply to knowledge in specific subject areas. Three tests possible on each test date. Many 4-year colleges require three SAT II tests; usually English, mathematics and a third of the student’s choice. The SAT II is offered on the same day as SAT I, but both may not be taken on the same day.