Increasing interest has recently emerged on the utilization of social software (Allen, 2004) by the educational community. This occurs not only due to the increased availability of social applications on the internet (e.g., web 2.0 services) but also because of their consistency to modern learning theories. Indeed, the use of social software for educational purposes is directly related to the sociocultural theory (Vygotsky, 1986) and to the social constructivism theory (Ernest, 1994; Kim 2001). These theories advocate the importance of the learners' interaction during active participation to learning activities which provide opportunities for design and construction of meaningful artefacts. Blogs ("Blog," n.d.) constitute special instance of social software that is a network application supporting groups of actors in communication and interaction. In a general overview of educational uses of blogs, Downes (2004) notices that students participating in blogging have opportunities to (a) reflect on their texts; (b) engage in writing for significant time intervals; and (c) trigger long dialogue with their readers leading to new writing cycles. In teaching and learning, the blogs can be used (indicatively) to ("Blog," n.d.): collect learning resources and share ideas and experiences; log notes and observations during an inquiry learning activity; manage a project; develop dialogue like in an online forum; reflect and communicate with teachers and peers-students; develop collaboration and social skills; obtain the motivation of writing for readers who comment you in order to participate more actively in the course; run online school newspapers, etc.
In Chen et al. (2005) the researchers integrated blogging with the learning portfolio approach highlighting the importance of the adoption of a well-defined pedagogical approach for the successful integration of blogs or any other content management model (e.g., wikis). The study of the impact of the kind of work or the genre of learning activity (e.g. project, problem solving, brainstorming, etc.) to blogging used for educational purposes appears as interesting field of research. In this direction Fesakis et al. (2008) studied the combination of blogs to learning by design pedagogical approach (Han & Bhattacharya, 2001) and claimed that teachers can utilize blogs in order to increase the communication and interaction among the students as well as enhance their participation and active engagement in the classroom. The research evidence showed that blogs fulfill the requirements of the learning approach in an acceptable level. Moreover, students claimed that the blog support for the learning by design activity communication and information management was decisive. Through the use of blogging students had increased opportunities to receive feedback though comments of both fellow-students and teachers. The blog assisted teachers in monitoring the evolution/progress of students' interactions, intervene whenever needed and obtain diagnostic information during the implementation of the appropriate assignments. The quantitative summarization of participants' interaction using time bubble charts for posts and comments and Social Network Analysis (SNA) for comments shows that students have been reading and commenting each other intensively during the activity. This graphical analysis of the students' interactions during blogging is a third research dimension in Computer Supported Collaborative Learning using blogs. The work of Fessakis et al. (2008) aimed at understanding the relation of collaborative electronic learning environment (blog) and the genre of assigned work (learning by design).
Learning by design is related to constructionism, according to which new knowledge is more effectively developed by students when they are actively engaged in the construction of an external, shareable artefact that helps them to reflect and collaborate. Learning by design emphasises the learning value of the artefact design and at the same time underlines the learning benefits of the process regardless of the final product. …