Background: Descriptive accounts of instruction in German vocational schools consistently indicate whole-class dialogue to be prevalent. We aim to extend previous research by elucidating pedagogically valuable dialogic practices that facilitate conceptual understanding, and by empirically investigating factors that promote or hinder student engagement in these practices. We focus on prior knowledge in the domain discussed, because knowledge differences count among the prime sources of heterogeneity among vocational students in Germany. However, with survey studies suggesting a decisive role of communication apprehension, we also intend to explore if feelings of uncertainty in ongoing verbal interactions moderate the knowledgeengagement relationship, while controlling for potential confounding and competing influences.
Methods:The study employs a longitudinal, multi-method design. It combines video recordings of nine consecutive lessons about Economic Business Processes in two classes, preceding tests on intellectual abilities and economic literacy, questionnaire reports of teacher-student relations and instructional clarity, and Continuous State Sampling during instructional activities. Interactional features were classified by applying a fine-grained category system that distinguishes coordinating gestures as well as types and qualities of dialogic exchanges.Results and discussion: Hierarchical regression analyses provide some evidence that getting opportunities to engage in valuable components of classroom dialogue depend on domain-specific prior knowledge. Differential teacher treatment exists in cold calling strategies and demanding follow-up techniques, even after controlling for students' gender. Moderated regressions for effects of prior knowledge and situational uncertainty on students' communicative behaviours indicate that advanced knowledge structures do not affect the mere quantity of a student's verbal contributions. But they robustly predict the degree of elaboration in given answers, together with positive teacher-student-relations, and net of the influences of student gender and instructional clarity. Feelings of uncertainty neither keep students from participating in classroom dialogue nor impair the quality of their contributions.
Open Access© 2015 Kärner and Warwas. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Kärner and Warwas Empirical Res Voc Ed Train (2015) 7:11 DOI 10.1186/s40461-015-0023-7 Page 2 of 26 Kärner and Warwas Empirical Res Voc Ed Train (2015) 7:11 Conclusions: Results suggest that domain-specific prior knowledge is not an indispensable prerequisite to contribute 'somehow' to classroom dialogue. However, it is a decisive...