The collaborative teaching method is a method that requires students working together in groups to solve problems to perform better in their studies. This paper aims to determine the method’s effectiveness in teaching Calculus I in UiTMCJ. Some students were chosen to participate in this study. They were taught Calculus I using this method and were assessed by using pre-assessment and post-assessment questions. The scores were analyzed using the paired T-test method. The results suggest that this method is effective to be used to teach Calculus I in UiTMCJ.