Bringing social media arenas, such as wikis, into the classroom invites teaching approaches that engage students in authentic, participatory and creative writing processes. This case study examines the online text production of primary school students in a wiki environment and how the key functionalities for commentary, discussion, logging skills of text and multimodal expression are utilized in practice to develop writing. Exploring the design of assignments and analysing the nature of final texts, writing strategies and feedback reveals an iterative process of writing dominated by strategies of expanding texts with new information and occasional surface editing. The students composed individual narratives on selected themes augmented by drawings, images, speaking avatars and video clips. Feedback was mainly provided by the teachers in the form of encouraging comments and corrective revisions directly in the students’ texts. Peer response was rare, in one project taking the form of discussion posts. Revising indicating increased language awareness was observed among second language learners. Overall, the study demonstrates a tension between instructional design, the affordances of the writing arena and the space for creativity when engaging students in advanced, participatory and reflective composing and revising of texts.