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This chapter first consolidates a set of important heuristic strategies used for constructing innovative scientific models from three books, including studies in the history of genetics and electromagnetism, and an expert think-aloud study in mechanics. Twenty-four strategies are identified, most of which are field-general. Patterns in their use suggest a partially organized hierarchy of interconnected strategies and substrategies, contrary to the view that heuristics are simply tried in random order. Strategies at four different size and time scale levels are described, including larger Modeling Cycle Phases of model generation, evaluation, and modification, each of which can utilize many smaller Tactical Heuristics as substrategies, e.g., analogy, or testing predictions from the model. These in turn can utilize Grounded Imagistic Processes, such as imagistic mental simulation, an important alternative to deduction for evaluating a model by running it. The framework links higher level, serially organized processes with lower level, imagery-based processes. Its intermediate degree of organization is neither anarchistic, nor fully algorithmic. Possible benefits of organization are narrowing the search space involved and balancing sources of model construction and criticism for productive creativity. Unorganized, spontaneous processes are also discussed, along with their possible benefits. 

Abstract Reasoning patterns found in Galileo’s treatise on machines, On Mechanics, are compared with patterns identified in case studies of scientifically trained experts thinking aloud, and many similarities are found. At one level the primary patterns identified are ordered analogy sequences and special diagrammatic techniques to support them. At a deeper level I develop constructs to describe patterns that can support embodied, imagistic, mental simulations as a central underlying process. Additionally, a larger hypothesized pattern of ‘progressive imagistic generalization’—Galileo’s development of a model or mechanism that becomes more and more general with each machine while still being imagistically projectable into many machines—provides a way to think about his progress toward a modern explanatory model of torque. By unpacking his arguments, we gain an appreciation of his skillful ability to foster imagistic processes underlying scientific thinking. 

Abstract: Reasoning patterns found in Galileo’s treatise on machines, On Mechanics, are compared with patterns identified in case studies of scientifically trained experts thinking aloud, and many similarities are found. At one level the primary patterns identified are ordered analogy sequences and special diagrammatic techniques to support them. At a deeper level I develop constructs to describe patterns that can support embodied, imagistic, mental simulations as a central underlying process. Additionally, a larger hypothesized pattern of ‘progressive imagistic generalization’—Galileo’s development of a model or mechanism that becomes more and more general with each machine while still being imagistically projectable into many machines—provides a way to think about his progress toward a modern explanatory model of torque. By unpacking his arguments, we gain an appreciation of his skillful ability to foster imagistic processes underlying scientific thinking. 

A central question for teachers is how to engage students in active reasoning while still aiming for substantial content goals. Asking students to generate and evaluate imagistic models can support both content learning and scientific thinking goals. Recent research indicates that imagery is a central component of scientific modeling (Schwartz and Heiser 2009). When discussing scientific models, teachers and students often lean heavily on words alone and overlook how modeling uses mental pictures and “mental movies.” Metaphorically, modeling processes can be thought of as occurring on a “sketch pad or video screen” of mental imagery in the student’s head. The set of strategies described here are intended to help teachers promote the kind of imagery that is used in scientific models. 

Abstract This paper describes model construction practices used by scientifically trained experts. Our work on science experts has involved analyzing data from videotaped protocols of experts thinking aloud about unfamiliar explanation problems. These studies document the value of nonformal heuristic reasoning processes such as analogies, identification of new variables, Gedanken experiments, and the construction and running of visualizable explanatory models. Although theses processes are less formal than formal deduction or induction or statistical inference procedures, the case study analyzed here shows that they can lead to real insights and conceptual change. At a larger time scale, the subject went through model evolution cycles of model generation, evaluation, and modification that utilized the heuristic reasoning processes above. In addition, the prevalence of imagistic simulation as an underlying foundation in these episodes suggests that it may be important to pay greater attention to an imagistic level of processing in the analysis of expert thinking. Larger time scale modes of model evolution and model competition were also evidenced. The analysis leads to four levels of processes or practices: IV. An overarching set of Model Construction Modes, primarily alternating between Model Evolution, in which a model is improved, and Model Competition, in which two or more models compete. III. Modeling (GEM) Cycle process of Model Generation, Evaluation, and Modification at a Macro level, as shown in Figure 10. II. Nonformal Reasoning Processes at a Micro level: e.g. analogy, running a model, identifying a new variable, and conducting a Gedanken experiment. I. Underlying Imagistic process including Imagistic Simulation that may have been occurring within all of the above processes. To our knowledge these four levels of processes have not been analyzed together in the past. They complement empirical processes of discovery, experimentation, and evaluative argumentation documented by others. Diagrams of how the above processes interact may give us some new ways to picture the roles of nonformal reasoning and imagistic processes during qualitative model construction. We call the set of processes at all four levels a 'Modeling Practices Framework'. Processes at a lower level serve as subprocesses for the level above it in this framework. Each level has multiple "things to try" to achieve tasks at the level above it. Thus the framework is an organized but flexible structure of heuristic processes. This lies between and contrasts with those who would describe theory making in science as either 'anarchistic', with no method structure, or 'algorithmic', with fairly standardized procedures. 

Abstract: This study investigates strategies teachers use to support mental imagery during modelbased science class discussions. A microanalysis of videos of classroom discussions was conducted in order to (1) identify and describe teaching strategies for supporting imagery; and (2) identify evidence that the students were engaging in the use of imagery as they constructed models and reasoned about competing models. This study starts from prior work on experts’ use of imagery, as well as from prior analyses of imagistic characteristics of concrete exemplars used successfully in a curriculum. Sixteen teacher support strategies for imagery are identified, along with thirteen student imagery process indicators. As the list of descriptors stabilizes, we are also identifying larger categories of descriptors—that is, structured categories of imagistic practices and categories of support. We present examples from a case study based on a transcript of a middle school discussion that served as one of the sources for our new organized set of imagery descriptors. 

Examination of matched whole class and small group discussions during use of an interactive physics simulation revealed that in the whole class discussions there was more time spent on important concepts, more time spent addressing student conceptual difficulties, and more episodes providing support for using visual features of the simulations. Abstract: This study investigates student interactions with simulations, and teacher support of those interactions, within naturalistic high school classroom settings. Two lesson sequences were conducted, one in 11 and one in 8 physics class sections, where roughly half the sections used the simulations in a small group format and matched sections used them in a whole class format. Unexpected pre/post results, previously reported, had raised questions about why whole class students, who had engaged in discussion about the simulations while observing them projected in front of the class, had performed just as well as small group students with hands-on keyboards. The present study addresses these earlier results with case studies (four matched sets of classes) of student and teacher activity during class discussions in one of the lesson sequences. Comparative analyses using classroom videotapes and student written work reveal little evidence for an advantage for the small group students for any of the conceptual and perceptual factors examined; in fact, if anything, there was a slight trend in favor of students in the whole class condition. We infer that the two formats have counter-balancing strengths and weaknesses. We recommend a mixture of the two and suggest several implications for design of instructional simulations.