Evaluation as a scientifically supported method for describing and assessing programs, measures, organizations, teaching, etc., has gained significant importance in Germany in recent years. The PISA 2000 international study questioned the quality of teaching in Germany and identified notable deficiencies. Evaluation of teaching can respond to this and positively shape the educational process. The evaluation of teaching refers to the attempt to capture the gradual implementation of new teaching methods and the incremental development of competencies among students through surveys and observations. This paper will first explain the theory of evaluation: conceptual reflection, forms of data collection, conflicts, and differentiation from diagnostics, as well as the teaching itself (goals of teaching).