Students’ Creation and Interpretation of Circuit Diagrams

Abstract

I report results of a study of representations of electric circuits and interpretation of
circuit diagrams by students in a class for pre-service teachers and graduate students in
science education. Students’ representations of circuits prior to instruction on the
conventions of circuit diagrams were collected and catalogued according to
representative characteristics and classified as either figural/iconic or abstract/symbolic
or a mixture. As might be expected, prior experience with circuits was related to the level
of abstraction in the ways students chose to represent circuits before standard circuit
diagrams had been introduced in the course. Students’ native competence was also
evident, however, as one student without prior experience developed her own abstract
scheme for encoding information in circuit diagrams and continued to use it after
conventional diagrams were introduced. Students were also interviewed as they
interpreted non-standard and conventional circuit diagrams. The interviews revealed that
previous experience with formal circuit diagrams, and the unstated but accepted
conventions therein, led to difficulties in treating an existing circuit diagram as a
completely abstract representation in one case, in contrast with expectations that
experienced students would recognize circuit diagrams as complete abstractions. These
results imply that students may be disadvantaged when conventional diagrams are simply
presented as the norm, without explicit discussion of representation issues.