Teaching algorithmic thinking using haptic models for visually impaired students

The Convention on the Rights of Persons with Disabilities demands inclusive education at all levels, including free access to education for disabled people and leading to an increasing heterogeneity of classes for teachers. Most of the tools used to teach algorithmic thinking and basic programming are oriented visually and hence badly or not at all usable for visually impaired. In this paper we propose a new method to introduce algorithmic thinking using a haptic model (e. g. LEGO plates and bricks) suitable for all students. We evaluated the method in a case study with 5 blind students, teaching them three basic search algorithms: linear search, binary search, and lookup in a binary search tree. It turned out that the haptic method facilitates the understanding of the underlying algorithmic ideas. Moreover it has the advantage to inhibit the common problem of thinking of many steps concurrently, because it forces the students to carry out the steps with their hands consecutively. This also facilitates the transfer from the model to the source code. Our new haptic method is a suitable way to teach visually impaired students basic algorithmic thinking. But furthermore it is also a promising approach for sighted students, because it addresses yet another sense.