The effects of cooperative learning on selected psychological and social traits were investigated. The sample of the study included 114 freshmen and sophomores in a psychology of learning and a fundamental mathematics course, in a public university in Turkey. The University of California-Los
Angeles Loneliness Scale (R-UCLA; Russell, Peplau, & Cutrona, 1980), the Toronto Alexithymia Scale (TAS; Taylor, 1984), the Liebowitz Social Anxiety Scale (LSAS; Liebowitz, 1991), the Self-Monitoring Scale (SMS; Snyder, 1972), and the Happiness Scale (HS; Fordyce, 1988) were used to assess
the levels of loneliness, alexithymia, social anxiety, self-monitoring, and happiness. Results show that cooperative learning was effective in reducing the levels of loneliness and social anxiety and increasing the levels of happiness among the participants. However, it was found that cooperative
learning was not effective in increasing students' self-monitoring skills or decreasing their alexithymia levels.