NAEP is an ongoing, congressionally mandated survey designed to measure what students know and can do. The goal of NAEP is to estimate educational achievement and changes in that achievement over time for American students of specified grades as well as for subpopulations defined by demographic characteristics and by specific background characteristics and experiences. In 1996, NAEP collected mathematics and science data from nationally representative samples of students in public and private schools in grades 4, 8, and 12. Additionally, directly comparable state assessments were conducted in public and private schools in participating states and jurisdictions at grade 4 for mathematics and at grade 8 for mathematics and science. (For many of the states and jurisdictions the sample of private school students was not adequate to support reporting of private school results. Accordingly, state-level results were reported by NAEP for the public school samples only.) State-level NAEP mathematics and science results are available for grade 8 public school students in 44 states and jurisdictions.
TIMSS is the largest and most ambitious study ever conducted by the International Association for the Evaluation of Educational Achievement (IEA). TIMSS is an international comparative study designed to provide information about educational achievement and learning contexts for the participating countries. Each participating country assessed mathematics and science in the two grades with the largest proportion of 13-year-olds (grades 7 and 8 in most countries, including the United States). Mathematics and science results are available for 41 countries for the higher of these grade levels--which, for convenience, will be referred to as the grade 8 level in this report. The U.S. TIMSS results are based on the sample of students from public and private schools.
In addition to the national results, three states opted to collect grade 8 data from representative samples of their students. Minnesota participated in a state-level administration of grade 8 TIMSS mathematics and science in 1995, while Missouri and Oregon participated in state-level administrations of grade 8 TIMSS in 1997. All three states also participated in the 1996 State NAEP. Thus, released public school NAEP results are available for all three states, as well as released TIMSS results for Minnesota. The TIMSS results for Missouri and Oregon have not yet been publicly released; however, preliminary data allowed some empirical verification of the linkage between NAEP and TIMSS.