Everyone uses a traditional five-point grading system to assess students' activities, however, it is not always possible to objectively evaluate students' work using this method. Therefore, the authors use the criteria-based student assessment system in our lessons. The purpose of this article was to compile a model of a system for assessing students' functional literacy based on a criteria-based approach. An experiment was conducted on 32 people and data was collected using observation and interviews. As a result of the study, it was revealed that the assessment system makes it possible to determine how successfully one or another educational material is mastered, or a certain practical skill is formed. Based on the conducted practical experiment, the effectiveness of the content-structural model of the system for assessing the functional literacy of students based on the criteria-based approach in computer science has been proved.