Comparing the use of a social annotation tool and a threaded discussion forum to support online discussions

This study aimed to understand how a threaded forum and asocial annotation tool, Diigo, supported online discussions. Forty-five pre-service teachers in two sections of an undergraduate course participated in two online discussion activities. A crossover study was conducted to examine student participation and interaction, and students' perceived learning experience in the two environments. In the first activity, students in Section A used Diigo for the online discussion while students in Section B used a threaded discussion forum. In the second activity, the two sections switched their online discussion environments. A participatory survey was administered at the end of the study. Postings in the two activities were analyzed and compared in terms of participation, focus, and interaction types. The results indicated that the different design of the two activities and the different functions of two environments impacted student participation, knowledge construction processes, and the foci of discussions. Social annotation tools could be used as an alternative environment to encourage certain types of interaction during online discussions.