ASSIST2009 was collected during the school year 2009-2010. Due to including duplicates when first released, the dataset was updated later. Based on the latest updated version, we remove users with less than three records, and remove the records without skills as well as scaffolding problems. After preprocessing, the dataset used in this article contains 283,104 interactions given by 4,151 students to a total of 16,891 distinct exercises and 101 skills.