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Session M4J

Using Students' Previous Experience and Prior Knowledge to Facilitate Conceptual Change in an Introductory Materials Course

Steve Krause, Jacqueline Kelly, James Corkins, and Amaneh Tasooji

Arizona State University

[email protected] , Jacqueline.Davis @asu.edu, [email protected] , and [email protected] Senay Purzer

Purdue University

[email protected]

Abstract - One important finding that the book, How People Learn, highlights is that all learning involves transfer from prior knowledge and previous experiences which can facilitate or impede learning. Learning can be facilitated by activating prior knowledge from an earlier class and/or context can be created for new material from previous experiences. Conversely, learning can be impeded by misconceptions that originate from personal experience, prior knowledge from previous classes, or inappropriate application of prior knowledge. Misconceptions from prior knowledge and previous experience can be classified according to their origin as a type of "impediment" to learning for which there are two general types, each with subtypes. Null impediment refers to missing information (necessary for learning new material) due to students: 1) not having prior knowledge (deficiency) or; 2) not recognizing links between new material and their prior existing knowledge (transfer). Substantive impediment refers to faulty concept models students hold from: 1) personal experience or observations (experiential); 2) prior courses and teaching (pedagogic) and; 3) bending or misinterpreting of new concepts to fit prior knowledge (misinterpretive). In this paper on research­to-practice we address the question of what learning strategies are most effective in repairing misconceptions or "impediments" of different origin. Index Terms ­ Conceptual change, learning strategies, misconception origin, prior knowledge, previous experience. INTRODUCTION The applied field of materials science and engineering (MSE) has, as a major goal of the discipline, educating students of other engineering disciplines on how to control a material's macroscale properties based on the understanding of its nanoscale structure. But, achieving this goal is a significant intellectual challenge to learners who must develop their own mental models (Boulter and Buckley, 2000) that effectively link the concrete "macroworld" of everyday objects and phenomena to the abstract "nanoworld" of atoms, molecules and microstructure. Students enter introductory MSE classes with a conceptual framework comprised of mental models. The mental models may arise from the prior knowledge acquired in an academic setting of earlier physical science and chemistry classes or from everyday previous experience where information might be acquired from personal observation, television, and the internet. When students' mental models do not align with scientifically correct consensus models of the scientific community they are referred to as misconceptions. These are scientifically inaccurate interpretations of the world that can neither explain nor predict the characteristics and behavior of the systems and phenomena of interest. Some examples of misconceptions include the explanation that copper metal is malleable because "individual copper atoms are malleable2 or that the metal nickel can only exist as a solid since "I have never seen Ni as a liquid or a gas." Such misconceptions can inhibit or impede conceptual change and learning. One important aspect of learning is how to modify a person's conceptual framework of macroscale-property / atomicscale-structure relationships such that faulty mental models are revised or replaced through conceptual change to a scientifically-accepted model. Different misconceptions can have different origins and characteristics that need to be addressed with different learning strategies. In order to facilitate misconception repair, Taber has created a classification system based on misconception origin as a type of "impediment" to learning. There are two general types, each with subtypes. Null impediment refers to missing information (necessary for learning new material) due to students: 1) not having prior knowledge (deficiency) or; 2) not recognizing links between new material and their prior existing knowledge (transfer). Substantive impediment refers to faulty concept models students hold from: 1) personal experience or observations (experiential); 2) prior courses and teaching (pedagogic) and; 3) bending or misinterpreting of new concepts to fit prior knowledge (misinterpretive). In this paper on research­to-practice we utilize Taber's

978-1-4244-4714-5/09/$25.00 ©2009 IEEE October 18 - 21, 2009, San Antonio, TX 39th ASEE/IEEE Frontiers in Education Conference M4J-1

Session M4J

classification method in conjunction with results from the Materials Concept Inventory for different pedagogies to assess the effectiveness of different learning strategies on repairing misconceptions of different origin. Overall, we want to develop a holistic understanding of what is the origin of knowledge and experiences students bring to introductory MSE courses, why this knowledge poses challenges for learning MSE concepts, and how more effective learning strategies can be implemented in MSE courses to enhance student understanding. BACKGROUND The book, How People Learn: Brain, Mind, Experience, and School (Donovan, Bransford & Pellegrino, 1999), summarizes and highlights important findings in cognition of teaching and learning. One finding is that students have prior knowledge about how the world works, consisting of preconceptions (or, if incorrect, misconceptions), and if their initial understanding is not engaged, they may fail to grasp the new concepts and information and revert to their preconceptions outside the classroom. A second finding is that novice learners are unlike expert learners in that experts have developed the learning skills to build a deep content understanding of their subject and have facts and ideas organized into a conceptual framework that facilitates their retrieval and transfer to new and different applications. A third finding is that experts are metacognitive learners who develop their own expertise by defining learning goals and monitoring their progress. In this paper we are mainly focused on the issues described in the first finding. In particular, since all learning involves transfer from prior knowledge and previous experiences, an awareness and understanding of a learner's initial conceptual framework on a subject and/or topic can be used to formulate the most effective teaching strategies. Constructivism refers to learning as conceptual change espouses the belief that students learn most effectively by constructing their own knowledge through modification of their conceptual framework for a given subject. The framework is comprised of mental models, which are simplified, conceptual representations that are personalized interpretations of systems or phenomena in the world around us. Useful mental models allow a learner to understand, explain, and predict behavior of systems and phenomena, whereas faulty mental models, which lead to misconceptions, cannot. Thus, characterizing a learner's initial conceptual framework since the learner's prior knowledge and previous experiences can facilitate or impede learning. For example, learning can be facilitated by activating a student's prior knowledge from an earlier class and/or a familiar context can be created for new material which can provide a linkage to a learner's previous experiences. Conversely, learning can be impeded by misconceptions that originate from personal experience, prior knowledge from previous classes, or inappropriate application of prior knowledge to new subject material. Conceptual change occurs during a student's development of a mental model, which is an iterative process of construction, evaluation, and revision or reconstruction of mental models of modeled target phenomena and systems. During model evaluation inconsistencies or deficiencies may cause the learner to revise his/her mental model or reject it and initiate a new one (Chin & Brewer, 1993). During model revision, it may undergo model addition, in which parts may be added to the existing model, or model elaboration in which it may be added to or combined with existing mental models, or model subsumption, in which it is embedded into a larger mental model (deKleer and Brown, 1983). During the mind's developing and manipulating a mental model, it may undergo many cycles of revision as it becomes clarified and detailed and, hopefully, more accurately representative of the modeled target system (Johnson-Laird, 1983). In fact, an effective teaching strategy is one which fosters conceptual change in which a student constructs a mental model that approaches the consensus model, one that has been agreed upon by scientists or groups of learners as the scientifically-accepted model or concept. Conceptual change is sometimes difficult and may be impeded by robust misconceptions resistant to change because of students' arguments, contradictions, and obstinacy (Niaz, 2005). Thus, the general strategies of assimilation or accommodation have been used to promote conceptual change (Dykstra, Boyle, & Monarch, 1992). The general strategy of assimilation is to build on existing mental models and associated concepts of a conceptual framework. In contrast is accommodation, in which change occurs by major revision or replacement of an existing misconception and associated mental model (Lakoff, 1993). Misconceptions must be identified before they can be analyzed and addressed. They may be revealed by a variety of methods such as pre-class questions, in-class questions, two-tiered questions (multiple choice plus open-ended explanation), student interviews, focus groups, and classroom talking, writing, and sketching. Instruments for measuring conceptual change, such as concept inventories, can then be created to evaluate innovative teaching strategies. In this work, a Materials Concept Inventory (MCI) has been used to assess conceptual change by calculating gain from pre-class and post-class administration of the MCI. There are several conceptual change theories that are commonly used by science and engineering education researchers5. Posner, Strike, and Gertzong's6 theory of conceptual change requires four conditions necessary for conceptual change to occur: 1) there must be dissatisfaction with the students' existing conception, 2) the new conception must be intelligible, 3) the new conception must be plausible, and 4) the new conception should be fruitful. The use of discrepant events had been used in the light of this theory. A common example involves demonstration of the buoyancy of a large and a heavy object such as wood in

978-1-4244-4714-5/09/$25.00 ©2009 IEEE October 18 - 21, 2009, San Antonio, TX 39th ASEE/IEEE Frontiers in Education Conference M4J-2

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water forcing students to reconsider the possible misconception that heavy objects always sink. More recently, new theories have emerged that focus more on understanding why some science concepts are so difficult for students to learn. For example, Vosniadou and Ioannides's7 "theory-theory" states that students form their own theories of science concepts which are sometimes in contrast with scientific theories. An example of such a misconception is the impetus theory that all moving objects have to have a force that acts in the direction the object is moving. diSessa3, on the other hand, argues that students have partial and fragmented understanding of concepts that he calls "knowledge in pieces." According to this conceptual change theory, a child can have a normative understanding of a concept such as thermal equilibrium in room temperature in one context (e.g., for wood) but not in another context (e.g., for metals). Chi's4 "ontological theory of conceptual change" is yet another theory that sheds light on the causes of robust misconceptions. According to Chi, concepts such as electric current and heat are difficult for students because they miscategorize these concepts as "things" rather than "processes." In addition to these theories that aim to describe the nature and causes of student misconceptions, there are also theories that inform teaching. A challenge for engineering and science educators is to decide which framework to use to study conceptual change. RESULTS In this work we have examined the origins of different types of misconceptions. We will also now consider their robustness and the effectiveness of different teaching strategies in repairing them. Qualitative and quantitative data were collected and analyzed from sections of the introductory MSE course taught in three different years. For classes in 2002 content was delivered by lectures, for 2003 by lectures and team-based discussions, and in 2007 by team-based hands-on activities, concept sketching and discussions, respectively. Results were collected from MCI testing, and student focus group discussions and individual student interviews. We will now describe the examples associated with the different origins. null-impediment-based misconceptions Null impediment refers to missing information (necessary for learning new material) due to students not having prior knowledge (null deficiency impediment): 1. Atoms in a solid: a) Cannot move, only electrons can b) May move through vacancies in a crystal lattice c) May move in the spaces between atoms in a crystal lattice d) Can move through both vacancies and in the spaces between atoms in a crystal lattice e) None of the above Null impediment refers to missing information (necessary for learning new material) due to students not recognizing the links between new material and their prior existing knowledge (null transfer impediment): 5. The melting points of most plastics are lower than most metals because: _______ a) covalent bonds are weaker than metallic bonds b) ionic bonds are weaker than metallic bonds c) Van der Waals bonds are weaker than metallic bonds d) covalent and Van der Waals bonds are weaker than metallic bonds e) ionic and Van der Waals bonds are weaker than metallic bonds 1) some properties of the three families of materials (metals, ceramics and polymers) are affected by the types of bonding between atoms or molecules for the three types of material families. Although all of the students have taken chemistry in the past MCI results show that the students do not distinguish the nature of the difference between atoms and molecules. The students have not transferred prior which makes this a transfer misconception that is not addressed by teaching by lecturing (0-5% loss). However, a moderate improvement is achieved (20-25% gain) by team discussions. A team-based, definition-oriented, conceptsketching learning task is being designed to address this misconception 9. The number of lines that connect opposite corners of a cube through its center is:_______ a) 2 b) 4 c) 6 d) 8 e) 12 10. In a cube there are *** sides and *** edges. a) 4 and 6 b) 4 and 8 c) 6 and 8 d) 6 and 12 e) 8 and 12 1) nature of the organization of atoms in a crystalline material, as characterized by its unit cell, can dramatically affect properties. As such, students need to understand the geometric characteristics of a given unit cell, but on the MCI pre-test many (40-60% correct) do not seem to even recall the geometric characteristics of a simple cube. However, homework problems, team discussions, and unit cell sketching address well this deficiency-based misconception (60-70% gain). 2) In the third example we consider the importance of materials processing, which can be done from solid, liquid and gas phases. However, MCI results and focus group discussions showed that most students believe that metals only exist in the solid or the liquid and solid phases for this

978-1-4244-4714-5/09/$25.00 ©2009 IEEE October 18 - 21, 2009, San Antonio, TX 39th ASEE/IEEE Frontiers in Education Conference M4J-3

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experiential-based misconception. MCI results showed little conceptual change for lecture (0-5%) but significant gains (75-80%) when teams discussed a materials processing learning task about the three phases. 4. Nickel can exist as: a) solid only b) liquid only c) gas only d) liquid or solid only e) liquid or solid or gas substantive-impediment-based misconceptions Substantive impediment refers to faulty concept models students hold from personal experience or observations (substantive experiential impediment); 15. If a small amount of copper is added to iron the electrical conductivity will change as shown: 1) 1) Concepts of saturation and supersaturation, which are broadly used in phase diagrams in MSE and also in prior courses in chemistry. Research has shown that in chemistry misconceptions saturation and supersaturation are robust and persistent. Similarly, MCI pre-post testing in MSE courses also shows that they are robust (5-10% gain) pedagogical misconceptions based on prior knowledge. Different teaching strategies in team discussions and learning tasks are ineffective in misconception repair, so planning is underway to introduce concept sketching and multimedia clips to improve conceptual change. 16. When three tablespoons of salt are mixed into a glass of water and stirred, about a teaspoon of water-saturated salt remains on the bottom. If a small % of salt is slowly added to the glass while stirring the solution, the change in concentration of the salt in the solution is given by curve:

Substantive impediment refers to faulty concept models students hold from bending or misinterpreting of new concepts to fit prior knowledge (substantive misinterpretive impediment): 18. After a piece of copper wire from a hardware store is heated it becomes softer. This is because: a) the bonds have been weakened b) it has fewer atomic level defects c) it has more atomic level defects d) the density is lower e) there is more space inside the crystal lattice 1) In the second example we consider an important phenomenon, permanent deformation in metals, which occurs by motion of 1-D defects across a crystal lattice. Students, however, believe that this deformation occurs because of bond changes (weakening or softening) in this misinterpretive-based misconception. MCI conceptual change results show conceptual change by lecture is ineffective (0-5% gain), while team discussions of a concept model show moderate improvement (35-40% gain), whereas team based concept sketching produces high gain (70-75%). DISCUSSION AND CONCLUSIONS Overall, results shown here demonstrate the importance of understanding not only the misconceptions that students hold, but the nature of their origin, as well as effectiveness of teaching strategy in repairing the misconceptions. Instruction in MSE classes could be more effective if

1) Incorrect prediction of macroscale properties by use of the macroscopic "rule of mixtures". This means that properties of a mixture of two or more materials have overall additive properties proportional to the volume fraction of the individual component materials' properties. Thus, if 1% copper (which has a factor of more than three times the electrical conductivity of zinc) is alloyed with zinc, macroscale "rule-of-mixtures" reasoning would predict a 3% increase in conductivity (3X conductivity x 1%). However, there is actually a 6% decrease in conductivity. The reason is that, at the nanoscale, there are many more atomic level sites for impurity scattering of electrons which is the cause for the reduction in conductivity. This example demonstrates the sometimes counterintuitive nature of understanding about materials' properties. When a similar question was posed on the MCI, only 20% of the students were correct on the pretest and 75% were correct answer on the posttest. There is still room here for more effective teaching and learning. Substantive impediment refers to faulty concept models students hold from prior courses and teaching (substantive pedagogic impediment)

978-1-4244-4714-5/09/$25.00 ©2009 IEEE October 18 - 21, 2009, San Antonio, TX 39th ASEE/IEEE Frontiers in Education Conference M4J-4

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instructors and textbooks were informed of student prior knowledge and experience, the effect of misconceptions on learning, and possible strategies for addressing them. Similarly, if prior classes, especially chemistry, were informed of prior knowledge and misconception issues, more effective learning would be possible in MSE courses. We have demonstrated a general classification scheme for origin of misconceptions based upon the underlying type of impediment. This classification scheme has the potential for broader application in other engineering disciplines. Thus, it may be possible to select a teaching strategy from the diagnosis of type and origin of misconception. Finally, the extended abstract will include more information and detail about these results, as well as progress in improving the MCI and the use of technology as a tool for learning. ACKNOWLEDGMENT The National Science Foundation supported this work via NSF CCLI Grant #0737146 and NSF IEECI Grant #083641. REFERENCES

[1] [2] Ben-Zvi, R., Eylon, B., & Silverstein, J. (1986). Is an atom of copper malleable? Journal of Chemical Education, 63, 64­66. Boulter, C. J., & Buckley, B. C. (2000). Constructing a typology of models in science education, in Gilbert, J. K., & Boulter, C. J. (Eds.), Developing models in science education. Dordrecht, Netherlands, Kluwer Academic Publishers. Chin, C. A., & Brewer, W. F. (1993). The role of anomalous data in knowledge acquisition: A theoretical framework and implications for science education. Review of Educational Research, 63, 1­49. DeKleer, J. and Brown, J. S. (1983) Assumptions and ambiguities in mechanistic mental models. In Mental Models, A. L. Stevens and D. Gentner (Eds.), Hillsdale, NJ: Lawrence Erlbaum Associates. Donovan, M. S., Bransford, J. D. & Pellegrino, J. W. (Eds.) (1999). How people learn: Bridging research and practice. National Academy Press, Washington, DC. Dykstra, D. I., Boyle, C. F., & Monarch, I. A. (1992). Studying conceptual change in learning physics. Science Education, 76(6), 615-652. Gilbert, J. (1995) The role of models and modeling in some narratives in science learning. 1995 Annual Meeting of the American Educational Research Association, San Francisco, CA. Johnson-Laird, P. N. (1983) Mental Models: Toward a Cognitive Science of Language, Inference, and Consciousness (Cambridge, MA: Harvard University Press). [9] Lakoff, G. (1993). The contemporary theory of metaphor. Metaphor and thought 2nd ed., In A. Ortony (Ed.), New York, NY, Cambridge University Press.

[10] Niaz, M. (2005). How to facilitate students' conceptual understanding of chemistry? ­ A historical and philosophy of science perspective. Chemical Education International, 6(1), 1-5. [11] Norman, D. (1983) Some observations on mental models. In Mental Models, D. Gentner and A. Stevens (Eds.), Hillsdale, NJ, Erlbaum. [12] Tan, Kim Chwee Daniel, Taber, Keith S., Liu, Xiufeng, Coll, Richard K., Lorenzo, Mercedes, Li, Jia, Goh, Ngoh Khang and Chia, Lian Sai (2008). Students' conceptions of ionisation energy: A cross-cultural study', International Journal of Science Education, 30 (2), 263-283. [13] Vygotsky, L. (1962) Thought and Language, T. Hanfmann & G. Vaka (Eds.), Cambridge, MA: MIT Press. [14] Monk, S., & Nemirovsky, R., "The case of Dan: Student construction of a functional situation through visual attributes." CBMS Issues in Mathematics Education, 4. (1994). [21] Lin, X., Schwartz D. L., & Hatano G., Toward Teachers' Adaptive Metacognition, Educational Psychologist, 40(4) (2005) 245-255.

AUTHOR INFORMATION Steve Krause is a Professor in the School of Materials, Fulton School of Engineering, Arizona State University, [email protected] Jacqueline Kelly is a graduate student in the School of Materials, Fulton School of Engineering, Arizona State University, Jacqueline.Davis @asu.edu James Corkins recently received his Ph.D. in Science Education, Department of Curriculum and Instruction, in the May Lou Fulton College of Education at Arizona State University, [email protected] Amaneh Tasooji is an Associate Research Professor in the School of Materials, Fulton School of Engineering, Arizona State University, [email protected] Senay Purzer is an Assistant Professor in the School of Engineering Education at Purdue University, [email protected]

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