Content knowledge and pedagogical content knowledge in Taiwanese and German mathematics teachers Thilo Kleickmann a, * , Dirk Richter b , Mareike Kunter c , Jürgen Elsner d , Michael Besser e , Stefan Krauss f , Marie Cheo g , Jürgen Baumert d a Leibniz Institute for Science and Mathematics Education, Olshausenstraße 62, Kiel 24098, Germany b Institute for Educational Progress (IQB), Hannoversche Straße 19, Berlin 10117, Germany c Department of Psychology, University of Frankfurt a.M., Senckenberganlage 15, Frankfurt am Main 60325, Germany d Max Planck Institute for Human Development, Lentzeallee 94, Berlin 14195, Germany e University of Kassel, Department of Mathematics Education, Heinrich-Plett-Straße 40, Kassel 34132, Germany f University of Regensburg, Department of Mathematics Education, Universit€ atsstraße 31, Regensburg 93053, Germany g National Academy for Educational Research (NAER), No. 2, Sanshu Rd., Sanxia Township, Taipei County 23703, Taiwan highlights  We assessed teachers' content knowledge and pedagogical content knowledge by tests.  For these tests, previous studies showed predictive validity for student outcomes.  The structure of subject matter knowledge was cross-culturally invariant.  German and Taiwanese teachers' CK and PCK reflected differences in teacher education.  CK and PCK in teacher subgroups reflected teacher selection processes. article info Article history: Received 10 September 2013 Received in revised form 30 September 2014 Accepted 14 November 2014 Available online 13 December 2014 Keywords: Teacher education Teacher selection Content knowledge Pedagogical content knowledge Measurement invariance International comparison abstract In comparing content knowledge (CK) and pedagogical content knowledge (PCK) of Taiwanese and German inservice mathematics teachers, the present study examines whether the two-dimensional structure of teachers' subject matter knowledge is cross-culturally invariant and whether differences in teacher education and in teacher selection are reflected in teachers' subject matter knowledge. The results confirm that CK and PCK represent two distinct, but correlated dimensions, even in teachers from completely different backgrounds. Taiwanese inservice teachers showed considerably higher CK and also higher PCK scores than German teachers. Teacher education and teacher selection should be considered important levers for reform in mathematics education. © 2014 Elsevier Ltd. All rights reserved. 1. Introduction The notion that teachers need a deep understanding of the subject matter taught at schools as well as knowledge about how to make this content accessible to students was prominently made by Shulman (1987). Following Shulman's arguments, content knowl- edge and pedagogical content knowledge had been considered to be core components of teacher competence (Ball, Thames, & Phelps, 2008; Shulman, 1987). Recent studies showed that indeed content knowledge and pedagogical content knowledge impact instructional quality and student progress (Baumert et al., 2010; Hill, Rowan, & Ball, 2005). Thus, teachers' levels of CK and PCK represent key levers for educational reform. Consequently, recent research addressed the question about the role of teacher education for teachers' subject matter knowledge, i.e. content knowledge (CK) and pedagogical content knowledge (PCK) (Kleickmann et al., 2013; Tatto et al., 2012). The international Teacher Education and Development Study (TEDS-M; Tatto et al., 2012), for instance, provided first evidence that structural * Corresponding author. Leibniz Institute for Science and Mathematics Education, Department of Educational Research and Methodology, Olshausenstraße 62, Kiel 24118, Germany. Tel.: þ49 431 880 3487. E-mail address: kleickmann@ipn.uni-kiel.de (T. Kleickmann). Contents lists available at ScienceDirect Teaching and Teacher Education journal homepage: www.elsevier.com/locate/tate http://dx.doi.org/10.1016/j.tate.2014.11.004 0742-051X/© 2014 Elsevier Ltd. All rights reserved. Teaching and Teacher Education 46 (2015) 115e126