Increasing Conceptual Understanding of Glycolysis & the Krebs Cycle Using Role-Play

Role-play is one way to give students a visual overview of glycolysis and the Krebs cycle, with the aim of helping them construct their own mental images. Students have reported that this technique has made it easier for them to understand the detailed biochemical reactions in their subsequent private study. The strategy of a choreographed dance as described in this article could also be considered a blueprint for teachers if they wish to construct a similar activity in a different topic which may be more relevant to their own students. Cellular respiration and metabolism are topics that are reportedly poorly understood by students and judged to be difficult by many teachers (Songer & Mintzes, 1994). Although these topics may not be required learning areas in some high school biology curricula, a grasp of fundamental concepts of cellular metabolic processes is advantageous for students undertaking (or intending to undertake) college-level studies in any biology-related course. There are three common difficulties in teaching cellular respiration: Students have a wide array of misconceptions which have developed from prior learning experiences (Driver & Bell, 1986); these misconceptions often persist after instruction perhaps due to the students' level of abstract or concrete operational cognition (Piaget, 1929); these misconceptions often remain intact throughout the undergraduate years despite repeated instruction at successively more advanced levels (Alparsian et al., 2003; Mann & Treagust, 1998; Seymour et al., 1991; Songer & Mintzes, 1994; Wandersee, 1983; Wandersee et al., 1994). Despite the acknowledged prevalence of students' misconceptions, particularly in the areas of photosynthesis and cellular metabolism or respiration (Wandersee et al., 1994), most instructors use "lecture-plus-wet-lab" as a teaching and learning strategy (Hodson, 1998). Although this dual role of a lecture/laboratory session where students develop their own learning skills and conceptual understanding is well established (Gunstone, 1995), laboratory sessions that are "wet" in character may not be effective in dealing with concepts that are molecular or submicroscopic and unable to be seen, but only imagined (Ross unpublished data). Compounding the problem, traditional laboratory exercises in these concept areas require students to also have skills which they have not yet developed--in observation, data analysis, equipment manipulation, and communication (Ragsdale & Pedretti, 2004). Even the most innovative of wet labs (Bolduc et al., 2002; Bullerwell & Hagar, 2003; Buttner, 2000; Korn & Tausch, 2001; Yip, 1998a) may not always provide the students with a link between what they observed at the macroscopic scale and molecular or submicroscopic scale (Lin & Hu, 2003; Ragsdale & Pedretti, 2004). Unhelpfully, teachers may be unable to make this link themselves (Yip, 1998b; Songer & Mintzes, 1994). If we are to assist students, and in some instances teachers, to overcome their misconceptions, there is a need to develop teaching and learning strategies that link these macroscopic and molecular (submicroscopic) scales (Lin & Hu, 2003; Ragsdale & Pedretti, 2004; Songer & Mintzes, 1994). It is also noted by Songer & Mintzes (1994) and Ragsdale & Pedretti (2004) that models and analogies are often effective methods to facilitate students' learning in difficult conceptual areas, thereby allowing them to make the links between the molecular and macroscopic levels. As one type of model, role-play has been found to be an effective method of facilitating learning experiences because this technique uses the student's creative and cognitive input at a number of levels (e.g., Lovejoy, 1995; Cherif & Somervill, 1995; Duveen & Solomon, 1994). This article is a description of a role-play where students act out some major parts of cell metabolism to gain greater conceptual understanding of glycolysis and the Krebs cycle by "being" a molecule or a key part in a dynamic cellular process. …