This paper examines peer rating result data for two consecutive core team-based first year engineering courses. Engineering students are inevitable to work in teams and the ability to effectively cooperate and communicate is increasingly recognized by technical corporations. Teamwork, an important learning objective and competency of ABET, is also progressively integrated into engineering courses. However, the effect of the length of students’ exposure into team-based projects training is not well studied. Given the ad-hoc experience, which is the more students experience teamwork, the better they perform in teams, we hypothesize that peer evaluation behaviors for the second team-based course will be better on average comparing to the first team-based course . This study will further help better bridge college students with industry in terms of teamwork competency. It will also inspire university administrators and instructors to design curriculums that help engineering students improve teaming skills.