YOCHIE WOLFFENSPERGER AND DORIT PATKIN Professional Knowledge of a Student It Takes two to Develop Professional Knowledge of a Student: A Case study Yochie Wolffensperger Dorit Patkin ABSTRACT: This case study examines the effect of coteaching on the development of a student's professional knowledge. The study analyses the student's perceptions of her experiences in a year- long seminar 1 course of math teaching in elementary school, conducted at a teachers' education college in Israel. The course was interdisciplinary and was taught jointly by two lecturers – one from the discipline of mathematics and the other from the discipline of academic literacy. Analysis of observations, interviews and documents illustrates the change in the student’s perception of her professional knowledge – both academic and practical – regarding math teaching as well as the contribution of caring coteaching to this change. The main conclusion of the study is that caring coteaching has considerably enhanced the student's professional knowledge. This conclusion is in line with the rather limited literature dealing with this topic. The present study investigates the perceptions of a student at a teachers' education college regarding the effect of coteaching on the development of her professional knowledge in the field of elementary school math teaching. The student on which this study focuses attended, together with additional students, a research seminar course of math teaching. The seminar course is the academic- professional turning point in teachers' education at the College. This is an annual course, which is highly complex and demanding, during which students are required to learn and develop their professional knowledge in the field of content as well as in pedagogy, while using high level academic literacy competences, such as inquiry and academic writing skills. The inherent, broad complexity of the seminar course (in the various disciplines) has in recent years given rise to collaboration between the lecturer in math teaching and a lecturer from the discipline of academic literacy in teaching during the course. The significance of this collaboration resides in the fact that, by using this way, students can acquire more diversified and consolidated tools required for performing the course's learning assignment. This collaboration is increasingly developing throughout the course and becomes more and more solid as a coteaching model (Cook & Friend, 1995) of both lecturers. The consolidation of this coteaching is advancing step by step in a process of trial and error (Murawski & Swanson, 2001) and includes every time an additional Teacher Education and Practice, Vol. 26, No. 1 / winter 2013, pp. 143-160 341