The aim with this master thesis is to analyze a scientific material concerning the context between learning and child/student development, and factors which controls process of learning, to create an image with quality account and teaching in mathematics, which then can raise the mathematical knowledge among students.

The phenomena which stand in focus for the investigation is: why there is a negative tendency for development of knowledge in mathematics, among the Swedish students that TIMSSs investigations showed in intercultural comparison within the years 1993, 1999, 2003 and 2007.

The method is the ethnographical method, which is based on: analyzing scientific theories about learning child/student development, factors which controls process of learning, and factors which controls process of learning the most and qualitative empiric investigation with qualitatively analyzes the questionnaires, which is about factors which are controlling the process of learning and factors which are controlling the process of learning the most.

Result of the theoretical and empiric analyzes shows that factors as school environment, attitude for subjects and teaching, controls and influence the learning. To end a unenthusiastic tendency as a negative development of mathematical knowledge among students that is shown in TIMSS investigation and to elevate the students' performance in mathematics, an elevated qualitative account and teaching in mathematics, by the factors named. Safe school environments as the intercultural meeting place, the teachers influence part to the students' subjects' attitude in mathematics and goal related grading criteria in teaching, is all required for e qualitative teaching in mathematics.