The TIMSS curriculum model takes into account three aspects: the intended curriculum, the implemented curriculum, and the achieved curriculum. These represent, respectively, the mathematics and science that society intends for students to learn and how the education system should be organized to facilitate this.

An international panel of mathematics and science education and statistician experts provided guidance for the general form the assessment frameworks should take. In each cycle several items of the test are made public and then replaced by new ones.

Tests designers, researchers and the education community can expect achievement data in mathematics and science to:

Extend and strengthen measurement of trends in mathematics and science begun in TIMSS 1995 and continued in TIMSS 1999.

Allow informed between-country comparisons of achievement and, in conjunction with other TIMSS data, suggest reasons for differences.

Enhance evaluation of the efficacy of mathematics and science teaching and learning within each country.

Highlight aspects of growth in mathematical and scientific knowledge and skills in the 2º year of ESO (14 year old students in Compulsory Secondary Education).

Provide data for secondary analyses about achievement levels in different education systems and schools, and about how to improve the teaching practice.