Trends in International Mathematics and Science Study (TIMSS) is an international assessment of student achievement in mathematics and science (TIMSS) at the fourth and eighth grades in different countries. PIRLS is an international assessment of student achievement in reading in the same grades. The studies are run by the International Association for the Evaluation of Educational Achievement (IEA) based at the IEA's International Study Center at the Lynch School of Education and Human Development, Boston College. The TIMSS assessments have been run every four years since 1995. African countries covered by the assessments in various years are Botswana, Ghana, Morocco, South Africa and Tunisia.