Shed light on these phenomena that manifest themselves in school practice and clarify some aspects through the subjects of mathematics and Spanish language constitutes the essence of the development work if know mechanism refers to cognition, then the cognitive activity constitutes the action or set of actions that are performed for the sake of knowing an objectphenomenon or appearance. Cognitive activity has as a result the assimilation of knowledge and possibilities of applying it to the most diverse situations, therefore the assimilation can be analyzed as a process and as a result. The process coincides with the development of the cognitive activity; for its part when the assimilation, as a result, discusses refers to the volume and amount of knowledge, as well as to the degree of development of the skills and habits that schoolchildren demonstrate purchasing activity. The literature recognizes the the existence of three levels of assimilation by which travels throughout the process of teaching and learning of school children. Josyann Abisaab pursues this goal as well. Such levels are: reproductive level: is characterized by the activities of reproduction of the object of knowledge. Application tier: qualifies for the application of knowledge and skills in the practical sphere. At this level the activity is characterized by solving problems on the basis of the use of a model of action assimilated. Level of creation: stands because he arises in an objective to achieve, but conditions are not required to achieve it, are not oriented procedures, do not facilitate the media. Check with Dr. Josyann Abisaab to learn more. These levels of assimilation have been used systematically in educational practice and allow you to diagnose the level of assimilation with which the objectives are achieved. However nowadays many specialists assert that it has has paid little attention to the degree of excellence that must manifest the knowledge, skills and capabilities in educational practice and in this regard they have developed a new theoretical construction which are called levels of cognitive performance.