Social media in education has the potential to enable new pedagogic student-centered ways by their bottom-up approach for supporting knowledge activities that harness collective intelligence unlike the hierarchical teacher-centered approaches. This paper discusses the opportunities and challenges posed by the fast growth of social media and the readiness for their adoption in education. It identifies the challenges which are included in educational use of social media. The paper presents the rationale of the SIMS (Social Media Networker) EU project. Primary data collected from both staff and students, across two countries (Greece and the UK), as well as secondary data from Finland are reported and analyzed. The paper concludes with lessons learned and provides guidelines for effective use of social media based on the core values of adoption, honesty, transparency and trust. Distribution of knowledge and responsibility is emphasized instead of centralization. The paper also suggests future research to understand the adoption issues of social-media-based e-learning.