A worldwide problem in Engineering education is the high rates of students' failure and drop out particularly at the beginning of the course. This is related to the process by which students learn Mathematics. An innovative methodology of teaching calculus was developed and it is presented in this paper. The approach, based on both course modularisation and the error theory, is student centred. It fosters student/lecturer commitment and emphasizes continuous assessment of the process. Knowledge, in this work, is regarded as a construction and reconstruction process based on phenomenological and hermeneutic concepts. Survey results demonstrated the effectiveness of the applied methodology. (Contains 3 figures.)