This method (cf. Beijaard, Van Driel, and verloop, 1999) has its origins in the narrative research with interest in people who express their meaning to phenomena by telling stories (narratives) about personal or professional life experiences. In an educational research context, such stories can provide information about teachers’ experiences regarding teaching specific topic. The story-line method focuses on a representation of these experiences in a two-dimensional diagram including two orthogonal axes. For instance, on the vertical axis, the evaluation of certain events or experiences can be indicated on a multi- point scale from negative via neutral to positive. This evaluation is plotted in time (years of teaching experience) on the horizontal axis. Teachers are asked to design their own story–line by putting dots in the diagram and connecting them. Three ideal-typical graphs can be distinguished : the progressive line (evaluations are going up), the stability line (evaluations do not change in time), and the regressive line (evaluations are going down). In reality, many teachers will design a story-line that has ups and downs. Teachers’ explanations of their story-line can include important information about the ‘tacit’ parts of their PCK, for instance, about backgrounds of their instructional strategies.