One of the problems that the English learners face in trying to improve the competency in English is the minimal opportunities to use it for real communication. Internet technology can offer help to solve the problems as by the use of social networking sites (SNSs) as Facebook, Twitter, Weblogs, Youtube, etc. Research found that those kinds of social network tools support educational activities by making interaction, collaboration, active participation, information and resource sharing (Selwyn N. , 2007). This study was aimed at seeing how on-line English discussion via Facebook could provide language learners with more opportunities to use the target language in an academic setting. The study was conducted in the English Education Department of Sultan Agung Islamic University. The subjects were the students taking the course of The Introduction to Second Language Acquisition. A Facebook group was created and the students were added as members. The teacher posted issues related to the course and asked students to discuss. Amazingly, many students took part in the discussion and presented elaborated arguments or comments; the ones that never happened in classroom discussions. The activities were observed and analyzed. It was concluded that facebook group could be a good place where learners have opportunities to use the target language, and in the same time, share knowledge on the subject matter.