Teacher Orchestration of Language and Gesture in Explaining Science Concepts in Images

Students’ difficulties interpreting diagrams remain a concern in science education. Research about improving diagram comprehension has included few studies of teachers’ orchestration of language and gesture in explaining diagrams—and very few in senior high schools. Research with younger students and studies of research scientists’ practice indicate the significance of the interaction of teachers’ gesture and language in explaining visualisations. The strategic deployment of such teacher-focussed authoritative explanations has been observed in facilitating progression to more complex and symbolic representations in classroom work. However, the paucity of such research in senior high school leaves open the question of how these teachers use gesture and language in managing the challenges of explaining the intricate sub-microscopic and abstract visualisations senior high school students need to negotiate. In this paper, we outline existing studies of teachers’ use of gesture and language to explain complex images in senior high school and investigate how it is managed by two biology teachers with images of different types and complexity representing the activity of certain cell components in the early phase of cell duplication. Implications are drawn for foci of further research including the role of a metalanguage describing different types of visualisations and their affordances.

Diagram comprehension ability of college students in an introductory biology course

College biology courses commonly use diagrams to convey information. These visual representations are embedded in course materials with the expectation that students can comprehend and learn from them. Educational research, however, suggests that many students have difficulty understanding diagrams and the conventions (e.g., labels, arrows) they contain. The present study evaluates biology students’ ability to comprehend scientific diagrams and the diagram characteristics that affect this comprehension. Participants were students in a physiology course who completed a multiple-choice test of diagram comprehension ability (DCA) (Cromley JG, Perez TC, Fitzhugh SL, Newcombe NS, Wills TW, Tanaka JC. J Exp Educ 81: 511–537, 2013). We coded the conventions used in each test diagram and used these codes to capture the diagram characteristics of conventions and complexity. Descriptive analyses examine students’ ability to understand scientific diagrams and which diagram characteristics cause the most difficulty. We also compared groups with low and high DCA scores to evaluate how students at different levels of comprehension ability are affected by diagram characteristics. Results show relatively poor DCA; the average total test score was only 69.5%. The conventions used in a diagram also affected diagram comprehension, and results show students had the most difficulty comprehending diagrams using a letter or numbering system, where arbitrary letters/numbers were used to signify objects and diagrams using cut-outs that showed cross sections and magnified interior views. Additionally, students’ comprehension was higher on diagrams with higher complexity (i.e., more types of conventions used), potentially indicating students are able to take advantage of the supports that different conventions provide. Implications for instruction are identified.