Although visual aids are widely considered a valuable source of scaffolding, the nature and active utilization of these aids in current science classrooms are not well understood. This qualitative study explores interaction in the teaching of concepts related to evolution, with a specific focus on a teacher's use of different visual support material. Based on a classroom study in a linguistically diverse Grade 4 classroom, we employed the perspective of discourse-bridging interaction to develop three broad categories of interactional examples, which we related to three kinds of visual support material used in the instruction: generic visual support images, naturalistic images, and disciplinary images showing examples of natural selection. The findings show that the interaction moved in and out of science discourse in a way that reflected the images' properties. A generic visual support image illustrated the concept of “adaption” as puzzle pieces fitting together, which promoted everyday and anthropomorphic examples of animals and people striving to fit in. When the teacher used naturalistic images, the discourse shifted between a range of perspectives, while visual aids and whiteboard drawings showing the classic examples of giraffes evolving (a disciplinary image) were employed to clarify the notion of natural selection. We discuss the study's implications for using visual support material in a planned way that supports disciplinary understanding.

中文翻译：

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四年级科学教学中的视觉资源和互动——探索进化和适应概念时的话语进出

尽管视觉教具被广泛认为是脚手架的宝贵来源，但这些教具的性质和在当前科学课堂中的积极利用尚不清楚。这项定性研究探讨了进化相关概念教学中的互动，特别关注教师对不同视觉支持材料的使用。基于在语言多样化的四年级教室中进行的课堂研究，我们采用话语桥接互动的角度来开发三大类互动示例，我们将其与教学中使用的三种视觉支持材料相关联：通用视觉支持图像、自然主义图像和展示自然选择示例的学科图像。研究结果表明，科学话语中的互动以反映图像属性的方式进出。通用的视觉支持图像将“适应”的概念阐释为将拼图拼凑在一起，从而促进了动物和人类努力融入的日常和拟人化例子。当老师使用自然主义图像时，话语在一系列视角之间转换，而使用视觉教具和白板绘图显示长颈鹿进化的经典例子（学科图像）来阐明自然选择的概念。我们讨论了该研究对以有计划的方式使用视觉支持材料来支持学科理解的影响。