Trends in International Mathematics and Science Study (TIMSS)
Indicators 15, 16, and 29 are based on data collected as part of the Trends in International Mathematics and Science Study (TIMSS). TIMSS provides reliable and timely data on the mathematics and science achievement of U.S. 4th- and 8th-grade students compared with that of students in other countries. TIMSS has been implemented four times: in 1995, 1999, 2003, and 2007. The focus of TIMSS is on the mathematics and science knowledge and skills of 4th- and 8th-grade students around the world. In 1995, some 41 countries participated; in 1999, some 38 countries participated; in 2003, some 46 countries participated; and in 2007, some 58 countries participated. TIMSS is closely linked to the curricula of the participating countries, providing an indication of the degree to which students have learned concepts in mathematics and science likely to be encountered in their schools. In addition to mathematics and science assessment items, TIMSS asked students, their teachers, and their school principals to complete questionnaires about their curriculum, schools, classrooms, and instruction. Indicators 15 and 16 feature TIMSS assessment data while data for indicator 29 are from the TIMSS 2007 Teacher Questionnaire.
In 2007, participating countries administered TIMSS to two national probability samples of students and schools, based on a standardized definition. Countries were required to draw samples of students who were nearing the end of their 4th or 8th year of formal schooling, beginning with Level 1 of the International Standard Classification of Education (ISCED). The ISCED was developed by the United Nations Educational, Scientific, and Cultural Organization (UNESCO) to facilitate the comparability of educational levels across countries and to assist countries in providing comparable, cross-national data. ISCED Level 1 is termed primary schooling, and in the United States is equivalent to the first through sixth grades. In most countries, including the United States, students who were assessed by TIMSS were in the fourth and eighth grades. Details on the grades assessed in each country can be found at http://nces.ed.gov/timss and additional information on ISCED levels can be found at http://www.uis.unesco.org/TEMPLATE/pdf/isced/ISCED_A.pdf.
In 2007, the assessment components of TIMSS tested students in two populations:
Fourth-grade student population. The international desired target population is all students enrolled in the grade that represents 4 years of schooling, counting from the first year of ISCED Level 1, providing that the mean age at the time of testing is at least 9.5 years. For most countries, the target grade should be the fourth grade or its national equivalent. All students enrolled in the target grade, regardless of their age, belong to the international desired target population.
Eighth-grade student population. The international desired target population is all students enrolled in the grade that represents 8 years of schooling, counting from the first year of ISCED Level 1, providing that the mean age at the time of testing is at least 13.5 years. For most countries, the target grade should be the eighth grade or its national equivalent. All students enrolled in the target grade, regardless of their age, belong to the international desired target population.
In the United States, TIMSS was administered between April and June 2007. The U.S. sample included both public and private schools, randomly selected and weighted to be representative of students across the nation. In total, 257 schools and 10,350 students participated at the fourth-grade level, and 239 schools and 9,723 students participated at the eighth-grade level. The overall weighted school response rate in the United States was 70 percent at grade 4 before the use of substitute schools and was 89 percent with the inclusion of substitute schools. At grade 8, the overall weighted school response rate was 68 percent before the use of substitute schools and was 83 percent with the inclusion of substitute schools. The final weighted student response rate was 95 percent at grade 4 and 93 percent at grade 8. Student response rates are based on a combined total of students from both sampled and substitute schools.
Achievement results from TIMSS are reported on a scale from 0 to 1,000, with a TIMSS scale average of 500 and standard deviation of 100. Even though the countries participating in TIMSS have changed across the four assessments between 1995 and 2007, comparisons between the 2007 results and prior results are still possible because the achievement scores in each of the TIMSS assessments are placed on a scale which is not dependent on the list of participating countries in any given year.
In addition to numerical scale results, TIMSS also includes international benchmarks. The benchmarks provide a way to interpret the scale scores and to understand how students' proficiency in mathematics and science varies along the TIMSS scale. The benchmarks describe four levels of student achievement in each subject, based on the kinds of skills and knowledge students at each score cutpoint would need in order to successfully answer the mathematics and science items. In general, the score cutpoints for the TIMSS benchmarks were set based on the distribution of students along the TIMSS scale. For more detailed information on sampling, administration, response rates, and other technical issues related to TIMSS data, see: http://nces.ed.gov/timss.