TIMSS has measured mathematics and science achievement at grades 4 and 8 every four years since 1995. Besides the tests, it collects questionnaires from school principals, from the sampled students’ mathematics and science teachers and, at grade 4, from parents. The school questionnaire covers resources, the school’s emphasis on academic success, discipline and safety, and the principal’s background; teacher questionnaires deal with preparation, professional development, job satisfaction and classroom practice. A curriculum questionnaire completed by national centres adds system-level context.
Türkiye first took part in 1999 and has joined every cycle since, apart from 2003. In TIMSS 2023 it tested 4,541 fourth graders and 4,925 eighth graders in 282 schools. Teacher data are linked to students, which allows classroom and school effects to be modelled; teachers are not sampled independently, however, so their responses describe the teachers of a representative sample of students. Analyses require the five plausible values and jackknife replicate weights. The free IEA IDB Analyzer manages both and also merges files.