The article describes common principles of the modern adaptive learning online systems. There is a list of features that a platform should have to provide online-courses in such format. Some of these features are data extraction and data analysis. Development of electronic educational resources center of Saint-Petersburg state university creates and maintains online courses which provide student learning data. Three platforms are considered: “Coursera”, “Stepik” and “Открытое образование”. These data were used for research modern educational platforms possibilities and the way of processing such data to see dependencies of the items and find the way to use this analysis for creating adaptive online-courses.