Students in an introductory educational psychology course used two WebCT communication tools (synchronous chat and asynchronous discussion) to discuss four case studies. In response to the item, "I learned the case studies best when using," 39 students selected synchronous chat and 51 students selected asynchronous discussion. Students who selected synchronous chat correctly answered fewer synchronously-discussed case study examination items than students who selected asynchronous discussion. Student perception of learning advantage may reflect personality characteristics such as sociability. If given free choice of online discussion tools, highly social students are likely to choose synchronous formats. Such a choice may result in decreased academic achievement. (Contains 4 figures.)