This research incorporated a collaborative teaching model into a selected ”introduction to design” course in order to explore its influences on students' learning effectiveness. The research subjects were selected from a polytechnic university in central Taiwan, and included 59 freshmen from the commercial design department and 57 from the spatial design department. After detailed analysis, the following conclusions have been drawn: (1) none of the pre-test results for any of the units in the professional theory have reached a significant level for students from either department. This means their pre-requisite knowledge for the introduction to design course is homogeneous. (2) The incorporation of a collaborative teaching model can improve students' learning effectiveness. (3) The students from the commercial design department have greater improvement in learning effectiveness than those from the spatial design department. (4) Both the teachers and the students showed a positive attitude towards the incorporation of the collaborative teaching model.