Mental Models Elementary Teachers Hold of Engineering Design Processes: A Comparison of Two Communities of Practice
Educating K 12 students in the processes of design engineering is a movement that is gaining in popularity in public schools. Several states have adopted standards for engineering design. Beginning in the mid 1990s, curriculum designers began producing curriculum units for all grade levels at an ever increasing rate, despite the fact that no common agreement exists on what should be included in the engineering design process used in K 12 education. Furthermore, very little pre service and in service professional development exists that will prepare teachers to teach a design process that is fundamentally different from the science teaching process found in typical public schools. This study provides a foundation upon which future studies about curriculum and professional development for engineering education can be based a glimpse into what teachers think happens in engineering design compared to articulated best practices in engineering design. Lave and Wenger's work with communities of practice and van Dijk's multidisciplinary theory of contexts as mental models provide the theoretical bases for comparing the mental models of two groups of teachers to the mental models of design engineers (including this engineer/researcher/educator) The first group of teachers teaches from textbook and/or kit based science programs. The second group teaches at least one unit in an engineering based curriculum. The design engineers include this engineer/researcher/educator as well as professional designers featured in a video. These elementary school teachers and this engineer/researcher/educator observed a video of the design engineering process enacted by professionals, then answered questions designed to elicit their mental models of the process they saw in terms of how they would teach it to their students. The participants' mental models are generated from their discourse using van Dijk's components of context models; they are displayed side by side in color coded columns. The key finding is this: Both groups of teachers embedded the cognitive steps of the design process into the matrix of the social and emotional roles and skills of students. Conversely, the engineers embedded the social and emotional aspects of the design process into the matrix of the cognitive steps of the design process. In other words, teachers' mental models show that they perceive that students' social and emotional communicative roles and skills in the classroom drive their cognitive understandings of the engineering process, while the mental models of this engineer/researcher/educator and the engineers in the video show that we perceive that cognitive understandings of the engineering process drive the social and emotional roles and skills used in that process. This comparison of mental models with the process that professional designers use defines a problem space for future studies that investigate how to incorporate engineering practices into elementary classrooms. Recommendations for engineering curriculum development and teacher professional development based on the results of this study are presented. Mental Models in the Design Disciplines and K 12 Education In 1943, Craik introduced the idea that people use mental models to make sense of and operate on the world. These small scale internal representations are functional rather than veridical, and underlie our perceptual, interpretive, predictive and explanatory interactions with the world. Merrill defines a mental model as a schema or mental representation combined with a process for manipulating the information in the schema (p. 17) People might be aware of some of the mental models they use, and some remain outside of conscious awareness. Researchers in many disciplines, including education, psychology, artificial intelligence, economics and the design disciplines (i.e. engineering, architecture, and urban planning) have explored theories that address adaptive and maladaptive representations of the world using mental models, drawing on Craik's work. In the design disciplines, the collaborative nature of design work requires that designers not only disclose their mental models, but represent them in a variety of modalities as well. This allows a design team to operate from a shared model of reality, to systematically test their shared model against reality, and to revise the shared model and their personal mental models as a result. For designers, what is learned and what is implemented is mediated by mental models that have been made explicit, which in turn leads to the revision of both the co created design and the designers' implicit mental models. In the design communities of practice, mental model(s) lead to mathematical, narrative, and graphical model(s) which lead to the final product the design and its physical embodiment. In 2005, the Design Council conducted a large scale study of the design process in eleven different companies and created a general description of the process. Furthermore, the design process was demonstrated by IDEO, a design and innovation consulting firm, for the ABC news show Nightline in a story that aired on July 13, 1999. The design process shown in the IDEO story, called The Deep Dive, represents best practices in design and is used to elicit participants' mental models. Implicit in a teacher's performance in the classroom are mental models of the content knowledge being taught, its enactment in the real world, and how that enactment might be framed for teaching (pedagogical content knowledge, metastrategic knowledge, and pedagogical design capacity) While a teacher is obligated to provide a set of experiences that lead students to key understandings and skills associated with a given curriculum, the teacher is not obligated to articulate for herself or disclose to others the mental model(s) that led to her particular enactment of curriculum in the classroom. Indeed, the teacher might not be aware of the mental model(s) that underpin her assumptions about content and procedural choices made in learning and teaching a curriculum. In K 12 engineering education, the classroom teacher must meld content knowledge and pedagogical content knowledge as she teaches a curriculum. A study by the National Academy of Engineering and the National Research Council revealed that "based on reviews of the research literature and curricular materials, the committee finds no widely accepted vision of the nature of K 12 engineering education" (p. 155) Katehi et al's findings also indicate that the field of K 12 engineering education lacks key research in the area of teacher professional 1 In this document, the words "engineering" and "design" as well as "engineer" and "designer," will be used interchangeably. development. I claim that understanding elementary school teachers' mental models of the engineering design process is an important step in designing appropriate curriculum and professional development for engineering education. I consider professional development as a design activity and will describe the mental model(s) teachers hold of the engineering process. These teacher mental model(s) represent a problem space and a starting point for possible design studies that address curriculum, professional development, and instructional support systems. Researchers now have described the engineering design process used by professionals in enough detail that some states have incorporated the engineering design process into their state education standards. This study references the design process in Massachusetts Science and Technology/Engineering Curriculum Framework. This design process consists of the following eight steps: identify need or problem, research need or problem, develop possible solutions, select best possible solution, construct a prototype, test and evaluate solution, communicate solution, and redesign. There are three reasons for using the design process in the Massachusetts Framework: 1) the state in which the study will be conducted, Missouri, does not yet incorporate the engineering design process into its state standards, 2) the engineering design process steps articulated in the Massachusetts Science and Technology/Engineering Curriculum Framework can be identified clearly in the Nightline story about The Deep Dive, IDEO's design process, and 3) the Massachusetts Framework was used in the creation of elementary engineering curriculum units that were used by some participants in this study. Furthermore, the engineering design process in the Massachusetts Framework is identical to the engineering design process that has been incorporated into the recently released A Framework for K 12 Science Education: Practices, Crosscutting Concepts, and Core Ideas. Theoretical Background and Research Design The theoretical basis for this study is the work of Wenger and Lave and Wenger on communities of practice as well as that of discourse analyst van Dijk on context models, which he equates to mental models. Lave and Wenger maintain that the development of expertise is socially mediated. Participants in a group of practitioners of a domain acquire identification with the practice embodied in the domain as they master peripheral roles at first, then progress to more central roles as ability and competence develop. The enduring nature of a community of practice comes from three characteristics of both community and practice: "mutual engagement, a joint enterprise, and a shared repertoire of ways of doing things" (p. 49) Mental models are more malleable, yet what makes them adaptive and effective in interactions within a community of practice is that they are strategically simple within a particular epistemic community. Practitioners' mental models influence their discourse along a few properties relevant to most communicative interactions within a community of practice: "the setting, the ongoi