The purpose of this study was to examine the extent of students' conceptual comprehension of electric circuits obtained during their high school years, as opposed to in recent class lectures. A total of 201 first-year university students majoring in Engineering in four introductory physics classes were involved in the study. A lecture demonstration of electric circuits was designed to achieve the study purpose. After observing the demonstration, the students were required to identify the associated phenomena and then explain the underlying physical laws. The students' reasoning performance was used to examine their conceptual comprehension. Two instructional strategies, group discussion without prior lecture and individual reasoning with prior lecture, were implemented to assess student performance. The findings disclosed that although the students had studied the topic previously, most of them could only identify the key phenomena involving simple principles, but failed to identify those involving profound ones. The models most of them adopted were scientifically acceptable but inappropriate in the given context. The students who engaged in group discussion appeared to have a higher phenomenon identification rate than that of the individual-reasoning group. Contrarily, the individual-reasoning group was found to have adopted the valid principles more effectively than the discussion group, probably due to the prior instruction received in the current class. The topics recently lectured seemed to have guided the students' cognitive orientations toward selecting principles, regardless of their validity. The study findings reveal that the concepts the students had acquired from their earlier learning were rather limited. That is, sophisticated instructional design is always pivotal, regardless of students' prior learning experiences. Moreover, when adopting demonstration as a teaching tool, explicit instructional guidance is also crucial.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)