Don’t blame the student, it’s in their mind: helping engineering students to grasp complex concepts

Context: The Thevenin Equivalent Circuit (TEC) concept has been identified as one of the first threshold concepts encountered by students in first year electrical engineering (Harlow, Scott, Peter, and Cowie, 2011). In order to assist students to learn about TEC, it is necessary to reduce the relational complexity of the concepts being taught (Halford, Wilson, and Phillips, 1998). The relational complexity framework reveals that under the traditional teaching method for TEC, nine different concepts are being combined, thus overtaxing the working memory of students. Methods for reducing relational complexity all incorporate chunking of several related cognitive units into more complex wholes, and sequential rather than parallel processing of information (Halford, Wilson, et al., 1998; Miller, 1956). These methods are essential elements of scaffolding (Wood, Bruner, and Ross, 1976).Purpose: It was hypothesized that introducing a scaffolding method for teaching TEC would improve students’ ability to learn over and above a traditional teaching method.Approach: First, the necessary background circuit theory was taught using simple component concepts (i.e. of relational complexity level 2 or 3). Then students were given practice along with class discussions about why things were done that way. For example, students were first given practice at finding the open circuit voltage of a network, before this concept was integrated with the other TEC concepts. Three trials were conducted, each with a control group that was taught TEC in the conventional way and a test group that was taught via the scaffolding method. After each lesson, students were given a TEC analysis problem that was scored on correctness. In the third trial, students in both conditions were asked to rate the difficulty that they would have in applying the TEC concept to a new problem.Results: The results showed that on each trial students scored slightly better when the scaffolding method was used, but these differences were not statistically significant, probably due to the large variance between the trials. In the third trial, scaffolding method students gave lower ratings than traditionally taught students on how difficult TEC would be to apply in practice. This result suggested that students’ learning experiences were better in the scaffolding method than in the traditional method.Conclusions: The scaffolding method presented here introduces students to new concepts in manageable and consolidated chunks, building up to complex concepts when students are ready. Students’ ratings suggested that better learning experiences occurred under the scaffolding approach. Future studies will adopt improved measures for determining the learning gains provided by the scaffolding approach.