Results of a Design-Based-Research Study to Improve Students’ Understanding of Simple Electric Circuits

Abstract

Most secondary school students fail to develop an adequate understanding of electric circuits as they tend to reason exclusively with current and resistance. Effective reasoning about electric circuits, however, requires a solid understanding of the concept of voltage. Against this background, a new teaching concept based on the electron gas model was developed with the goal to give students a qualitative but robust conception of voltage as a potential difference that causes the electric current. Using an air pressure analogy, the teaching concept aims to provide students with intuitive explanations that have their origins in the students’ everyday experiences, e.g. with bicycle tires or air mattresses. Similarly to these everyday objects, where air pressure differences cause an airflow, voltage is introduced as an electric pressure difference across a resistor that causes the electric current. An empirical evaluation with 790 secondary school students shows that the new teaching concept leads to a significantly better conceptual understanding than traditional teaching approaches in Germany. Furthermore, 12 of the 14 participating teachers state that they plan to teach according to the new concept in future as they consider it to be a significant improvement.