Usage of The Models
Step 1: It is recommended to teach the topic of simple electric circuits in the class the usualway, followed by solving some problems. After the topic is presented, the model should be introduced.
Step 2: The teacher should previously construct an example of the 3-D model as shown
in Figure 4 or Figure 5 and then explain how the model is related to what has been instructed before. The instructor should emphasize that the battery increases the potential that drops
across the resistors, and the potential is the same everywhere on wires connecting resistors or any other element of the circuit.
Step 3: As always, working in groups enhances the students’ understanding and
minimizes the teachers’ involvement. Therefore, it better allow students to work in groups.
Once the groups of three or four students are formed, it is time to construct the 3-D model of the circuit. The initial skeleton frames of the circuit that the students will construct need not
to be as complex as described in Figure 2 and Figure 3 so as to make them get familiar with the model building. Students can initially construct the three-dimensional model of the
circuits by using wires. It is also necessary for the teacher to give some guidance in the
beginning of the building of the model. It is crucial to emphasize that the voltage rise in the
3-D model is represented by the heights of the wire corresponding to the battery.
Step 4: As a quick informal test of the usefulness of the 3-D model building
methodology, a circuit similar to the one in Figure 6 can be presented to the students. For this
study, the 10th grade students were asked to compare the electric potentials of points K, L, M
and N in Figure 8. Most of the students (15 out of 22) could give the correct answer to this
question. Parenthetically the achievement test didn’t include this question.