Scaffolding a (T)-GEM: Magnetic Fields and Current

“ The inquiry processes evident in GEM included students’ finding patterns in information, generating hypothetical relationships involving three or more variables, evaluating the empirical consistency of information, coordinating theoretical models with information, and making predictions.” (Khan, 2007, p.898)

Khan (2007) purposes a learning model for students to gain first hand experience defining and refining relationships between variables. Although T-GEM provides a explicit framework, however, something seems to be lacking. When Khan (2007) inspected the teacher’s verbal response, it became clear that specific teaching strategies are required. Instead of identifying skills as teaching methods, scaffolds are a more fitting variable. Upon closer inspection, the T-GEM pedagogical model works harmoniously with problem solving scaffold foci outlined by Kim & Hannafin (2011). In combination, the teacher’s scaffolding role is made more specific and applicable.

Here is a design that provides suggestions about scaffolding prompts according to each step of the GEM cycle. Students will investigate the relationship between the strength of the induced field, current voltage, relative distance to the current, the direction of field and Earth’s magnetic field.

Students inquire about:

• Strength of electromagnetic field changes relative to the current (i.e. current voltage and position of compass)
• Strength of electromagnetic fields in relationship with flipped currents (i.e. current voltage & electromagnetic field)
• Strength of induced fields (Investigate the relationship between strength of the induced field, current voltage, relative distance to the current, direction of field and Earth’s magnetic field.

Using the simulation from the Gizmos (i.e. Magnetic Induction), students can manipulate the voltage of the current and the position of the compass. Students will observe how the needle moves relative to voltage and location to the probe. The needle is parallel to the magnetic field lines.

G – Generate Hypothesis

Problem Solving Phrase: Exploration

Scaffold foci: problemization & internalization

In the case of T-GEM, students are asked to consult a data set, identify patterns and generate a hypothesis. This is consistent with the exploration phase of problem solving. Khan (2007) emphasizes that students are asked to propose a defining statement about the relationship between concepts. Kim & Hannafin (2011) supports that during exploration, students benefit from embedding scaffolds that ask students to identify anomalies and conflicting evidence.

Using the Gizmos (i.e. Magnetic Induction), students can place compasses around a wire. The simulation allows students to explore and change the voltage and the location of the compass. More specifically, students can observe the changes of a compass and the corresponding values when placed in multiple locations around the wire, when current is set at:

• 0 amps
• 60 amps
• -60 amps

Students are asked to make an explanatory statement about the relationship between the direction of the needle, the voltage and the direction of the compasses.

 

E – Evaluate

Problem Solving Phase: Reconstruction

Scaffold foci: Internalization, generalization

In this phase, students’ hypothesis is taken to a test. More specifically, proposed models are confronted with new information. Khan (2007) expresses that this is a key phase where original models are challenged. Inferred conceptual relationships are refined in order to be applicable to new contexts. Here, it is important to support students with “[s]caffolds [that] help guide students to challenge their thinking, consider alternative evidence, and evaluate alternate solutions.” (Kim & Hannafin, 2011, p.410) The scaffolds that can support this will help reduce and or alter misconceptions. “[S]tudents generate and revise potential solutions and explanations as they encounter confirmatory or contradictory evidence.” (Kim & Hannafin, 2011, p.410)

To refine thinking model, students switch to magnetic field view, observe the following:

What happens the the compasses under these conditions…

• Same current: far vs. close to the current
• Same location: strong vs. weak current

This time, students click on the view show magnetic sensor. Record the change in values.

M – Modify

Problem Solving Phase: Reflection & Negotiation & Presentation & Communication

Scaffold foci: collaboration, feedback

This phase shares many similarities with the discussion part of a study. In light of the observations, students make inferences and informed predictions about the ways in which the variables interact. Students are to reflect upon their experience and offer an explanation about observations. Often through in-depth reflection, it may initiate new insights and investigations. However, it can be difficult to connect evidence to theory. Therefore, students may benefit from collaborating with peers. Thus, scaffolding foci for the presentation and communication problem-solving phase assist in helping students solicit feedback and inspire new ideas. Moreover, content scaffolds will help make relationships more explicit. Content prompts can also help students refine their models. When discussing about electromagnetic fields, understanding the science behind the induce fields from a running current may support learning (e.g. Magnetic field and wire; Faraday’s Law etc.). Since these new models requires confirmation, this inspires a new cycle of GEM.

 

 

Reference

Khan, S. (2007). Model-Based Inquiries in Chemistry. Science Education, 91(6), 877-905. doi:10.1002/sce.20226

Khan, S. (2011). New Pedagogies on Teaching Science with Computer Simulations. Journal Of Science Education & Technology, 20(3), 215-232. doi:10.1007/s10956-010-9247-2

Kim, M. C., & Hannafin, M. J. (2011). Scaffolding problem solving in technology-enhanced learning environments (TELEs): Bridging research and theory with practice. Computers & Education, 56(2), 403-417.

Gizmos – Magnetic Induction https://www.explorelearning.com/index.cfm?method=cResource.dspDetail&ResourceID=611

Mag Lab – Magnetic field around a wire 2

https://nationalmaglab.org/education/magnet-academy/watch-play/interactive/magnetic-field-around-a-wire-ii

Phet – Faraday’s Law – https://phet.colorado.edu/sims/html/faradays-law/latest/faradays-law_en.html