The evaluation of education systems has switched from "coverage in each level" to testing "achievement or aptitudes”. Most Latin-American countries are testing their students from the first grades of primary (and even preschool) to the end of the university studies. At the school level the target is switching from "classifying" students (those who could advance to the following level and those that had to repeat), to helping each student to learn at least the minimum necessary to be promoted (if the student has the required capacity, even though its previous knowledge is limited). There are signals of an increasing interest to evaluate not only achievement in "instruction" (contents, abilities and aptitudes), but that also the "formation" (education properly so), that is to say, the capacity to make responsible decisions according to well accepted criteria.

These changes have generated impacts in the goals and operation of the education institutions and have created gaps between the initial formation of the teachers and the social demands by quality of the education. For teachers to "help students to improve" they need detailed information on the aspects that each one of her/is students have mastered and those abilities or knowledge that they need further remedial teaching and personal work. Without detailed information teachers cannot identify what teaching processes must be changed or how to help each student. Further help to students, therefore, demands revising (and eventually redefining) the objective of each national tests used to measure the quality of the education.