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mechanism, expert-novice, teaching, explanation, biology, modeling, science education


This document is intended for use by instructors and their students. The activity contains steps to introduce students to the MACH model involving analyzing and discussing explanations about biological mechanisms. Initially, students read modified articles about biological mechanisms during class, although instructors may prefer to assign readings outside of class before the activity. During the activity, students are required to analyze the readings for evidence of research methods, analogies, context, and mechanisms. In so doing, students learn how to integrate the information pertaining to each of the MACH model components into a coherent explanation about their biological mechanism. After performing the above activities individually, students discuss findings in pairs, and then share their ideas with the class. After discussion, the instructor presents the MACH model. In our experience once the above activity has been successfully completed, students show strong evidence of competence in the writing of explanations about mechanisms. Details of the tetrahedral MACH model, and its related class activities, are freely available in the Purdue International Biology Education Research Group (PIBERG) ePubs collection. Together with the description of the activity, we have included advice on suggested topics, citations of suggested readings, and examples of typical student analyses of such readings. This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.