Introduction

The Importance of Country and School Contexts in Making International Comparisons

The results of high quality international assessments such as TIMSS 2015 can make important contributions to improving educational quality. Yet it must be kept in mind that countries differ from one another in fundamental ways, and educational systems reflect these differences. TIMSS has the specific goal of increasing understanding of the effects of educational policies and practices within and across countries, and expends substantial effort to address the more substantive and important questions about the meaning of the achievement results.

The TIMSS 2015 Encyclopedia provides an overview of the context in which learning mathematics and science takes place in each country. A country’s education system is the result of a series of decisions made in response to the specific goals, priorities, politics, resources, and historical traditions of its government representatives and citizens, and the information in the encyclopedia provides an opportunity to better understand each participant’s contexts for mathematics and science instruction.

Fifty-seven countries participated in TIMSS 2015, including some distinct education systems that always have participated separately throughout IEA’s long history (e.g., the Dutch-speaking community of Belgium and Hong Kong SAR). In addition, TIMSS 2015 had seven benchmarking participants, including two Canadian provinces; one U.S. state; two emirates from the United Arab Emirates; Buenos Aires, Argentina; and Norway, benchmarking its lower grades.

Countries and benchmarking participants could elect to participate in the fourth grade assessment, the eighth grade assessment, or both. Forty-eight countries and 7 benchmarking participants administered the fourth grade assessment, and 40 countries and the 7 benchmarking participants administered the eighth grade assessment.

Nationally representative samples of approximately 4,000 students from 150 to 200 schools participated in TIMSS 2015 at each grade. More than 312,000 students participated in TIMSS 2015 at the fourth grade, and a further 270,000 at the eighth grade.