The article presents a correlative model based on the Piagetian phenomena and student with special educational needs. Approaches are indicated allowing the mental age to be defined by applying Jean Piaget’s experiments, as well as doing it vice versa – defining the stage as per Jean Piaget in determining the IQ of the individual. The proposed model allows the general education teacher and also the individual progress development team in school, to get easily oriented on the capabilities of the student with special educational needs and prepare individual programs adequate to the student’s development.