BTRecurTutor: a Tutorial for Practicing Recursion in Binary Trees

Recursion in binary trees has proven to be a hard topic. There was not much research on enhancing student understanding of this topic. We present a tutorial to enhance learning through practice of recursive operations in binary trees, as it is typically taught post-CS2. We identified the misconceptions students have in recursive operations on binary trees. We designed a code writing exam question to measure those misconceptions. We built a tutorial that trains students on avoiding those misconceptions through the use of a semantic code analyzer that detects misconceptions and provides appropriate feedback. Our results show an improvement in student performance when using the tutorial along with the practice exercises, and even more improvement when the same exercises are used with a semantic code analyzer. The best way to use our tutorial to enhance student performance on advanced recursion is to allow students solving the tutorial exercises with the the semantic feedback.