The English curricula in Taiwan are increasingly moving to an exam orientation, for the effectiveness of the lessons directly impacts through exams upon the academic lives and prospective careers of college students. This paper first reviews previous studies regarding the preparation courses for TOBIC. It then introduces the course design of some in-sessional TOBIC preparation courses for college students and evaluates the effectiveness of the courses by comparing students' scores in the pre-test and post-test, conducting a satisfaction survey and interviewing students about the program and perceptions of their improvement or lack of it. The pre- and post-tests are official tests and the overall score gain of 56 after the 52.5 hours of lessons, two practice tests and 6-hour TA tutorials is extremely successful (p<.OOOI) compared to the gains recorded in previous studies. The anonymous satisfaction survey indicates that students are very satisfied with the program (4.3 on average on a five-point Likert scale). One-on-one interviews with 15 high-achievers and 15 non-achievers explore some relevant topics qualitatively. This study further discusses possible reasons for the test results and makes some suggestions for future TOEIC preparation courses.