Fuzziness is a concept that was suggested in 1965 by Prof. Zadeh that has improved rapidly until today and it has successful applications in many fields. The reason why it has such successful applications in many fields is that it allows expression and analysis of the problems we encounter in daily life more realistically and therefore it produces more realistic solutions. Thus, the concept of fuzziness and the theories suggested and the methods developed on this concept are gaining importance day by day. The creation of suitable learning conditions for students is of great importance in the method of problem based learning system. The most important of these conditions is the suitable composition of student groups for the purposes of instruction. Especially while carrying out performance evaluations, the opinion formed about the student is both quite difficult to turn into numerical expressions and vary according to each instructor. Thus, there exists the requirement of a system in which the performance evaluations will be carried out verbally in a more suitable way for human structure of thinking and in which numerical results will later be obtained by using this information.