School accreditation ratings reflect student achievement on Standards of Learning Assessments and other tests in English, history/social science, mathematics, and science. Ratings are based on the achievement of students on tests taken during the previous academic year and may also reflect a three-year average of achievement. Adjustments also may be made for students with limited English proficiency and for students who have recently transferred into a Virginia public school. Accreditation ratings also may reflect the success of a school in preparing students for retakes of SOL tests.