On Idealizations and Models in Science Education

Abstract

Idealizations are omnipresent in science. However, to date, science education research has paid surprisingly little attention to the use of idealizations in fostering students’ model competence and understanding of the nature of science (NOS). The starting point for the theoretical reflection in this paper is that insufficient consideration of idealizations in the science classroom can lead to learning difficulties. The following discussions should help to clarify the terms idealization and model and their relationship to each other. An example is drawn from physics. At least two cases can apply when considering model usage in the classroom. In the first case, to understand an observed phenomenon, a model (as a representation) of the situation to be explained is constructed. At this point, it is necessary to perform idealization. Seemingly, this step is still neglected in much of the science education literature but is well addressed in the philosophy of science. In the second case, existing models to work with are introduced, perhaps alongside a real experimental situation. This approach is called working with models in science education. This paper focuses primarily on the first case. Against the background of model building, a positioning and conceptual approximation of idealizations take place. To organize the idealization process, a framework of several categories of idealization adopted from science philosophy is offered. The framework is intended to stimulate explicit reflection about how models are constructed. The construction of a model by idealization is illustrated through an example from geometrical optics. Finally, the considerations presented are discussed in the context of the literature, and suggested research topics are provided.

The ‘thin lens’ in the light of idealisations

“…We have discussed the importance of idealisations in this context at length elsewhere [11]. Since we are talking about a frequently used model in this paper, we will only highlight the following consideration.…”

“…A framework for structuring idealisations based on [16]. Reproduced from [11], with permission from Springer Nature.…”

On the ball on a string demonstration of angular momentum conservation

“…Instructors of physics are quite familiar with the role that approximations, simplifications, and idealizations play in physics education [1][2][3][4][5][6]. These techniques help to simplify complex systems and make them more accessible to students, allowing them to solve problems that would otherwise be beyond their mathematical abilities.…”

“…However, it is important to consider the extent to which these idealizations are realistic and how real-world systems may differ from these idealizations. The use of idealizations is common in basic physics, such as ignoring friction, air resistance, and the mass of strings and springs, and considering most objects as 'point particles' [3]. While introductory physics courses often include a laboratory component, the level of analysis required to account for complicating factors may be limited [7].…”

“…While introductory physics courses often include a laboratory component, the level of analysis required to account for complicating factors may be limited [7]. In fact, learning to identify and employ such idealizations is arguably an important part of learning how to 'think like a physicist' [3,[7][8][9].…”