Prediction assessments: Using video-based predictions to assess prospective teachers’ knowledge of students’ mathematical thinking Anderson Norton • Andrea McCloskey • Rick A. Hudson Published online: 12 March 2011 Ó Springer Science+Business Media B.V. 2011 Abstract In order to evaluate the effectiveness of an experimental elementary mathe- matics field experience course, we have designed a new assessment instrument. These video-based prediction assessments engage prospective teachers in a video analysis of a child solving mathematical tasks. The prospective teachers build a model of that child’s mathematics and then use that model to predict how the child will respond to a subsequent task. In this paper, we share data concerning the evolution and effectiveness of the instrument. Results from implementation indicate moderate to high degrees of inter-rater reliability in using the rubric to assess prospective teachers’ models and predictions. They also indicate strong correlation between participation in the experimental course and prospective teachers’ performances on the video-based prediction assessments. Such findings suggest that prediction assessments effectively evaluate the pedagogical content knowledge that we are seeking to foster among the prospective teachers. Keywords Teacher knowledge Á Instrument development Á Video Á Preservice teacher education Á Pedagogical content knowledge Introduction Since Shulman’s (1986) seminal work on the topic, pedagogical content knowledge (PCK) has become a central focus of mathematics teacher education. Researchers have addressed PCK by designing various approaches to supporting teachers’ professional development. A. Norton Department of Mathematics (0123), Virginia Tech, Blacksburg, VA 24061, USA e-mail: norton3@vt.edu A. McCloskey (&) Penn State, 268 Chambers Building, University Park, PA 16802, USA e-mail: amccloskey@psu.edu R. A. Hudson University of Southern Indiana, 8600 University Blvd, SC 3261, Evansville, IN 47712, USA e-mail: Rhudson@usi.edu 123 J Math Teacher Educ (2011) 14:305–325 DOI 10.1007/s10857-011-9181-0