This study aims to investigate the effects of synchronous online discussions in foreign language classrooms, using a control group (face-to-face oral role play) and an experimental group (synchronous online discussion), on the development of English productive skills, such as speaking and writing. The case study employed a pretest-posttest quasi-experimental design. Thirty students from Danang University of Medical Technology and Pharmacy participated in the research project. Data were collected includes pre- and post- treatment tests at the beginning and at the end of the semester, pre- and post-questionnaires; and semi-structured interviews. Results derived from a t-test analysis revealed that there were no statistically significant differences between the two groups in either speaking or writing proficiency at the end of the semester. However, both groups showed a significant gain in speaking and writing proficiency between the beginning and the end of the semester. Statistics indicated significant levels between pre- and post-treatment scores reached by the nonsynchronous computer mediated communication role play and the synchronous computer meddiated communication chat groups.