Currently, comprehensive school teachers of the Republic of Kazakhstan pay special attention to assessment system of pupils' knowledge based on personally oriented approach. In work "A black box: what there inside? An assessment of knowledge of pupils as a way of increase of efficiency of teaching and educational process" P. Blek and D. William note that "Improvement of quality of training at schools is one of important state priorities... initiatives for the purpose of improvement of planning and management, statement are more whole, more careful and frequent inspections--all this... doesn't give desirable feedback in improvement of teaching and educational process at school the conclusion arises: something in this scheme isn't enough... In our work we try to glance in a black box. We in detail consider such aspect of training as "the forming assessment" which is a basis of effective training". Today became quite obvious that in modern Kazakhstan education the traditional system of estimation of proficiency of pupils was insolvent. The assessment cult instead of a cult of knowledge dominates. Similar situation--result of the Former Soviet approach to system of estimation of pupils which assigned a duty to have an appreciation on all subjects to each pupil, and only three points from five are carried to that. In a 5-mark scale of estimation applied in Kazakhstan such points, as "2" and "1"--negative. The similar perception formally narrowed a 5-mark scale to the 3-mark. As a result teachers of schools are compelled by points "3", "4", "5" and the estimated judgments corresponding to them to estimate pupils of different level and different degree of readiness. This system of estimation operates on pupils of both comprehensive schools, and gymnasiums, lyceums, establishments of the correctional developing type. To distinguish these marks which are put down in documents on education as practice shows, it is simply impossible that is a serious contradiction. As a result we receive unauthenticated of an assessment of quality of training in general. Kazakhstan signed in 1999 the Bologna convention, is on the threshold of new educational reform--transition to 12 years' education. For this period different systems of estimation were considered: 10-mark, 12-mark, 100-mark, test and modular system [5] and others. In this article we present the results of the pilot study on assessment system of rural schools in the Republic of Kazakhstan, Aktobe region Kenkiyak village. Having chosen the theme of the experiment: "Control and evaluation activities in conditions of transition to 12-year education system" a working group of teachers-experimenters chose one of its directions for detailed study - the rating evaluation system. At present in all territories of Kazakhstan a five-point evaluation system has been introduced, which may not always estimate the each child's individual development trajectory. The new evaluation system is introduced in order to create optimal conditions for efficient tracking of individual pupils' achievements using a rating evaluation system. The object of research throughout the work is the learning process of Mathematics, Cognition of the world, Chemistry, Russian and Kazakh languages in forms 3-8. Total in the experiment 10 forms were involved. The experiment took place during three years from 2009 to 2012. Results of conducted research were those changes in the teaching process, which have caused qualitative characteristics such as increased digestible material and depth of its understanding, the activity of pupils at the lesson, their creative independence, change of self-criticism and self-evaluation, etc. Rating assessment system allows to create maximal comfort environment of learning and upbringing, allows to transfer learning activities of pupils in internal need. The particular importance is the educational aspect of the new evaluation system for the pupil--from the self-discipline and to focus on his own interests and needs.