Education is one of the priority directions in the development of our state. It is impossible to talk about modernization of education without monitoring its quality. The article considers a differentiated approach to learning, the conditions under which this approach can be applied. Two main criteria of the differentiated approach are singled out: level of training and learning ability. The article gives recommendations on the phased implementation of differentiation. Positive and negative parties of different types of control of education quality are also presented. Most objective is the differentiated test control. The article reveals its characteristics, the possibilities of using it in lessons in primary school.