Project Dates: 2010 – present
The Bifocal Modeling Framework
Figure 1. Bifocal Modeling Framework linking a physical experiment and a computer model.
Bifocal Modeling is an inquiry-driven science learning approach that challenges students to design, compare and examine the relationships between physical experiments and computational models (thus, “Bifocal”). Students explore natural phenomena such as heat diffusion, chemical reactions, and bacterial growth through physical experimentation, computer models, and the comparison of both in real time. Bifocal Modeling also offers students opportunities to design their models and simulations, instead of only interacting with them.
Bifocal Modeling differs from other educational uses of modeling and simulation because it brings in empirical data in real-time, so the comparison with the model is tightly incorporated into the curricular unit. This is different from using lab experiments only for confirmation of theoretical content. The range of classroom possibilities for Bifocal Modeling accommodates many types of activities. In a typical unit, students explore a phenomenon by developing or exploring two parallel implementations: a physical experiment and a computer model connected through a sensor. This design enables students to quickly identify the similarities and differences between the two, which achieves two goals: on the content side, they can more readily understand and refine their theories and models. On the meta-modeling side, students can reflect about the nature of models, their limitations and applications, the role of error and error correction, and how scientists create laws and equations based on noisy data.
General Structure and Activities
In the Bifocal Modeling Framework (BMF), the physical and computer components are divided into the following sequence of activities:
- Design – Within the scope of the phenomenon under investigation, students formulate the questions they would like to answer, generate testable hypotheses, and design their physical experiments as well as the computer model to be used in conjunction with it. In designing the model, students typically define the possible variables and conceptualise rules or equations to model the phenomenon of interest.
- Construct – To determine the nature of the phenomenon under study, students construct an apparatus for their physical experiment and the corresponding computer model.
- Interact – Students interact with their physical experiment by collecting data (e.g. with embedded sensors). Similarly, they interact with their computer model by changing its parameters, running the model, observing the results, and recording the data.
A complete Bifocal Modeling activity comprises the use of many different tools and techniques as well as different modes of classroom facilitation, so the application of the framework within a classroom setting may be challenging. In some contexts, to overcome such challenges, curriculum designers and teachers might combine differently real and virtual experimental setups utilizing ready-made or student-designed models. Teachers may select among these combinations to adapt the implementation modality to their particular needs and requirements.
