Annotating educational discussion boards to help students who are blind

Educational discussion boards are growing in use as they help students share knowledge and doubts in a working/studying environment. Although these interactive tools are shown to be highly effective in learning environments, their usability by blind students is very poor. The major challenge remains to be able to organize the structure of discussion boards in a way to make the navigation easier. In this paper we focus on the challenges associated with accessibility of discussion boards. In particular, we develop techniques to improve accessibility of educational content for students who are blind. Threads of messages in discussion boards evolve with new postings, thus just by investigating the subject headings or contents of earlier postings in a message thread, a blind student may not be able to guess the contents of the postings deeper in the hierarchy. In order to overcome the navigation obstacle for users, it is essential to develop techniques that help identify how the content of a discussion board grows. We develop a technique to organize messages in a message board, by automatically classifying and annotating postings to guide users through discussion segments relevant to their navigational goals.