Students in the Rotman Business School are generally very studious, so do not be surprised if you are expected to work 40h a week as an exchange student. The university organizes "competition cases" every month to create emulation between the students.Students can take part to competition in lots of subjects. 
The students associations are very present in the campus and organize reunions every week in the Rotman's atrium. Most associations are business associations.
Students also like to meet in bars every Thursday (Thirsty Thursday) and to go together in nightclubs after the mid-term exams and after the final exams.
Even if there are few parties and few leisure associations, the atmosphere is very friendly and exchange students are quickly integrated.