ABSTRACT
Previous research has established that teaching students to understand the functioning of electric circuits on a qualitative level is a difficult pedagogical challenge (e.g., Lee & Law, 2001; McDermott & Shaffer, 1992; Reiner et al., 2000). First, the central concepts, such as voltage, current and resistance, are very abstract by nature and refer to processes that are dynamic and often intangible in natural situations. Consequently, it is not easy to provide the students with accurate information about electric circuits in an easily comprehensible format. Second, students have many misconceptions about electric circuits which seem to be exceptionally tenacious and resistant to teaching efforts (e.g., Lee & Law, 2001; McDermott & Shaffer, 1992). The problem is that the students are not well aware of the limitations of their initial model, which is often coherent enough for them to feel that they have arrived at a consistent (albeit incorrect) and satisfactory explanation (Vosniadou, 2002). According to some of the recent studies, the use of computer simulations
seems to promote students’ conceptual understanding of electric circuits more effectively than the use of real circuits (e.g., Finkelstein et al., 2005; Jaakkola & Nurmi, 2008; Zacharia, 2007). Finkelstein et al. (2005), for instance, examined the effects of substituting a computer simulation for real circuits on learning the basics of DC circuits in a university physics course. They found that the students using the simulation outperformed the students using the real circuits, both on a conceptual knowledge test and in the coordinated tasks of assembling a real circuit and describing how it works. One explanation why computer simulations seem to promote conceptual
understanding more effectively than real circuits, seems to be that the development of a theoretical understanding of electric circuits through practical manipulation with real circuits can be problematic; in many cases students can only see what is happening on the surface level of the circuit, while being unable to grasp the underlying processes and mechanisms that are important for theoretical understanding (e.g., current flow) (Finkelstein et al., 2005; Hennessy,
Deany, & Ruthven, 2006). In comparison with real circuits, a simulation can make the functioning of electric circuits more transparent; it can model circuits on various levels of abstraction (e.g., a circuit in schematic format vs. the mimicking of real bulbs and wires) and visualise processes that are invisible in natural systems1 (Finkelstein et al., 2005; Goldstone & Son, 2005; Hennessy et al., 2006). This visualisation allows the students to become better aware of the limitations of their initial reasoning (the output of the simulation may be in conflict with their expectations) and discover the properties of the scientific model embedded in the simulation (e.g., the electric circuit is a closed system in which all components interact; Ohm’s law; total resistance in parallel and series circuits) (e.g., de Jong, 2006; Lehtinen & Rui, 1996). Another distinctive feature of computer simulations is that the embedded model(s) often highlights the elements that are important for theoretical understanding (e.g., interdependence between current, voltage, and resistance) and excludes (or hides) the elements that are irrelevant or potentially misleading (e.g., poor connections, worn batteries, tangled wires, colour of wires, or even broken wires or bulbs) (e.g., Finkelstein et al., 2005; Goldstone & Son, 2005). Our own findings suggest that, at least in the elementary school context,
computer simulations and laboratory activities should be considered as complementary (rather than competing) instructional tools that, in combination, can provide appropriate conditions for conceptual change and deeper understanding of electrical circuits (Jaakkola & Nurmi, 2008; Jaakkola, Nurmi, & Veermans, in press; see also Ronen & Eliahu, 2000). In our first study (Jaakkola & Nurmi, 2008) fourth-and fifth-grade students solved circuit assignments in three different learning conditions – a computer simulation (using only a simulation), a hands-on laboratory exercise (using only real circuits) and a simulationlaboratory combination (using the simulation and the real circuits in parallel). In each condition the students had 90 minutes to practice with the circuits during the intervention. The results showed that the development of conceptual knowledge was the most notable in the combination condition. Students in the simulation condition also made clear progress during the intervention, but their conceptual understanding of electric circuits did not reach the desired level in the post-test. The progress was the most modest in the laboratory condition where the students’ conceptual understanding remained at an elementary level, even after the intervention. In a more recent study (Jaakkola et al., in press) we investigated the role of implicit and explicit instruction (see the section on method, page 137) on students’ conceptual learning outcomes when they used the simulation either on its own (simulation environment) or in parallel with real circuits (simulation-laboratory hybrid environment) to learn the basic principles behind the functioning of electric circuits. The main finding was that although the explicit instruction was able to improve students’ conceptual understanding of electrical circuits considerably in the simulation environment, their understanding did not reach the level of the students who used the simulation and the real circuits in parallel, even after the amount of time spent on constructing
and studying the circuits during the intervention was controlled (see Table 7.1 for main results; more details are provided in Jaakkola et al., in press). The aim of this chapter is to investigate from video data the issues that could
explain why combining and linking the use of virtual external representations (a computer simulation) with concrete external representations (laboratory activities) seems to promote students’ conceptual understanding so effectively. The analysis focuses on the three theoretical issues outlined below.
