This study investigated the concept images of blind students about the polygon concept. For this purpose, four open-ended questions were asked to five blind middle school students. During the interviews, geometric shapes were presented with raised-line materials and blind students were given opportunities to construct geometric shapes with…

Assigning difficulty level indicators to the knowledge units helps the learners plan their learning activities more efficiently. This paper focuses on how to use the topology of a knowledge map to compute and rank the difficulty levels of knowledge units. Firstly, the authors present the hierarchical structure and properties of the knowledge map.…