The use of 3D virtual worlds for instruction allows educators to design synchronous instruction to students around the world. In such learning environments, students being in virtual bodies and assuming roles in virtual identities perform instructional tasks successfully which are more challenging to realize in a traditional classroom. The aim of this study is to explain the roles of the teacher, students and the social environment, and to discuss the consequences of the instruction in terms of the instructional method and the effect of the three dimensional virtual environment during a foreign language activity. The study group was chosen among students attending two Anatolian High Schools in Izmir in 2010-2011 Fall semester. The activity was conducted with 12 students, six of whom are from each school. The research method is the case study, one of the qualitative research methodologies. The data was collected through interviews, observation and dairy, and the content analysis was performed. This study presents how to design an instructional foreign language activity by using six thinking hats technique in Second Life environment. Owing to the six thinking hats technique used in Second Life, students go through an active thinking process, and search the ways to find strong evidence in order to support their ideas.