To keep improving education, we need to know how students compare. The Trends in International Mathematics and Science Study (TIMSS) is part of a series of international studies, sponsored by the International Association for the Evaluation of Educational Achievement, to measure trends in student achievement. More than 60 nations participate in TIMSS. 

TIMSS is sponsored by the International Association for the Evaluation of Educational Achievement (IEA). The U.S component of the study is conducted by the National Center for Education Statistics (NCES).

• Westat performs the data collection for NCES.
• TIMSS collects comparative data on achievement in mathematics and science from samples of 4th and 8th graders.
  • In 2015, TIMSS also assessed grade 12 students who had taken or were taking calculus and physics.
  • In 2017, TIMSS piloted the new eTIMSS assessment to try out the digitally based assessment and to evaluate mode effects.
  • In 2019, TIMSS will conduct the first digitally based main study assessment.
• Change is measured within and between countries in these areas by administering TIMSS every 4 years. Additional information is obtained relating to the cultural environments, teaching practices, curriculum goals, and institutional arrangements that are associated with student achievement.

• Outcomes from TIMSS studies have been used to inform national and local policymakers, industry leaders, and educators, particularly about the comparisons across countries and over time in student achievement.