Teaching with Playdough
Science of Learning: Why It Works
Three-dimensional models can help to improve students' understanding of geological phenomena. Physical models, such as playdough models, serve as analogies to geological features and geologic maps. Analogies support the development of spatial thinking skills by allowing the student to draw from their knowledge and apply it to new cases (e.g., Gentner 1983). For example, students can reason from what they can experience when carving off pieces of playdough to how erosion will reveal geological structures). Analogical learning also applies to "mapping" -- that is, relating -- the features of models onto real world phenomena (e.g., this layer of playdough corresponds to a layer of sandstone). Physical models provide analogies to real-world phenomena, support cognitive offloading, and promote spatial accommodation.
Practice constructing spatial analogies can help students develop the mental models that allow them to recognize new cases of familiar concepts in the field. When instructors provide accurate physical models of geologic features, students can self-assess their understanding by comparing their mental model -- or their own physical model -- to the instructor's physical model. When students make their own physical models, these models serve as a means of "inscription," in much the same ways that mapping and sketching do: they allow for students to record their conceptual understanding of a natural phenomenon (Mogk and Goodwin, 2012). However, unlike mapping and sketching, a playdough model allows for this record to be three-dimensional, like the phenomenon itself, which can reduce the cognitive demands inherent in the process of inscription by reducing the need to generate a 2D representation of 3D space (Newcombe, 2012). In addition, physical models support spatial accommodation: when a student compares their (mental or physical) model of a phenomenon or region to their instructor's model and recognizes a difference between the models, the student is prompted to revise their mental model (Davatzes et al., 2008). When the change required is spatial the student may use the feedback directly to revise the model. When the change is significant, the student may need to completely discard their old model and construct a new one. Playdough models of geological structures can thus serve as the basis for improved mental models.
In addition to supporting students' understanding of 3D geological phenomena, student-made playdough models also show instructors what students are thinking. A quick walk around the classroom while students are making models lets an instructor complete a formative assessment of student understanding. If student models are accurate, you can move on to the next course topic or activity. If their models illustrate some misconception(s), you can see that and address it immediately.
With careful attention to detail, playdough models can be built to scale. This allows students to measure model features directly on the models, which can be used as a means to check calculated values.
One of the benefits of using playdough in the classroom is that it is affordable and re-usable. Requiring students to buy a 4-pack of Play-Doh for a course is reasonable if you make use of it often. If they are careful about sealing the containers it will last them all semester.
One of the biggest challenges in having students make playdough models is conveying what aspects of the model are critical. For example, we have seen students make models with exaggerated dips (for stratigraphic contacts, faults, or other features) and extremely steep "erosional surfaces." This can lead to models that don't illustrate the phenomena we want to illustrate; the models that are not strong analogies for the geologic features we want students to understand. Students build more useful models when we both describe and show them the geometry of the model we want them to build.
Teaching activity collection
We have a collection of 9 teaching activities that utilize playdough models for teaching and learning about 3D geologic phenomena and the maps we use to depict those phenomena:
- Modeling Unconformities
- Introduction to Structure Contours
- Introduction to Igneous Intrusions
- Introduction to Modeling Faults
- Introduction to Modeling Folds
- Modeling Folds: Block Diagrams and Structure Contours
- 3D Model of a Geologic Map
- Isopach Maps
- Wakemup Pluton
Davatzes et al. (2018). Learning to form accurate mental models. Eos, 99, https://doi.org/10.1029/2018EO091643. Published on 07 February 2018.
Gentner, D. (1983). Structure-mapping: A theoretical framework for analogy. Cognitive Science, 7(2), 155–170.
Mogk and Goodwin (2012). Learning in the field: Synthesis of research on thinking and learning in the geosciences, in Earth and Mind II: A synthesis of research on thinking and learning in the geosciences, edited by Kim A. Kastens and Cathryn A. Manduca. GSA Special Paper 486:131-163. DOI: 10.1130/2012.2486(24)
Newcombe, N. S. (2012). Two ways to help students with spatial thinking in geoscience. Geological Society of America Special Papers, 486, 85-86.