Using an Intelligent Tutoring System to Teach Red Black Trees

There are many tutoring systems that are being used to teach basic concepts in grade schools and high schools. There are few that address the issues involved in teaching complex skills and concepts such as are taught in CS2. We designed, developed and implemented an intelligent tutoring system (ITS) to help teach the concepts underlying red black trees. Red black trees are a balanced tree structure that are created and maintained with fairly complex insertion and deletion algorithms. The ITS helped the students improve their understanding of red black trees and also changed the instructors view of the causes of the students' difficulties. This paper describes effects on student learning, the lessons we learned from using the ITS and how it affected the way in which teach red black trees in our class. We have used the ITS for four years in our data structures class and it has benefited us in many ways.