The aim of this paper is to describe and analyse the repurposing of Facebook into a tool for learning in teacher training, and how information literacies are enacted in the process. The study is informed by a socio-cultural view on information literacy which implies that learning and literacies are situated, tool-based practices. An ethnographic study of a Facebook Group with two hundred Swedish teacher trainees and two educators is conducted. Five semi-structured interviews contextualize and validate the online material. 201 conversations from the Group during April and May 2012 are analysed using the theoretical concept appropriation and the empirical lens of information literacy. The Facebook Group can be appropriated as a problem-solving tool and a relation-building tool. Depending on the mode of appropriation, different information literacies including different conceptions of credibility are enacted in the Facebook Group.