Core Ideas and Topics: Building Up or Drilling ... - ACS Publications

Feb 15, 2017 - recognizable topics in the context of a general chemistry course. We show how commonly taught topics can be supported and developed on ...
0 downloads 7 Views 1MB Size
This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes.

Article pubs.acs.org/jchemeduc

Core Ideas and Topics: Building Up or Drilling Down? Melanie M. Cooper,*,† Lynmarie A. Posey,† and Sonia M. Underwood‡ †

Department of Chemistry, Michigan State University, 578 South Shaw Lane, East Lansing, Michigan 48824, United States Department of Chemistry & Biochemistry, and STEM Transformation Institute, Florida International University, 11200 SW Eighth Street, Miami, Florida 33199, United States



ABSTRACT: In this paper we discuss how and why core ideas can serve as the framework upon which chemistry curricula and assessment items are developed. While there are a number of projects that have specified “big ideas” or “anchoring concepts”, the ways that these ideas are subsequently developed may inadvertently lead to fragmentation of knowledge, rather than construction of a coherent, contextualized framework. We present four core ideas that emerged as a consequence of a transformation effort at our institution and discuss the relationships between core ideas and more recognizable topics in the context of a general chemistry course. We show how commonly taught topics can be supported and developed on the basis of the core ideas and discuss why this approach can lead to a more expertlike framework upon which students can build their future understanding. KEYWORDS: First-Year Undergraduate/General, Second-Year Undergraduate, Chemical Education Research, Curriculum, Student-Centered Learning, Learning Theories FEATURE: Chemical Education Research



INTRODUCTION One of the best documented ideas in teaching and learning1 is that experts in a discipline have different knowledge structures than novices. That is, experts tend to have organized coherent frameworks in which knowledge is contextualized and linked making it accessible and useful while novices’ knowledge and understanding tend to be fragmented and disconnected. The question we are concerned with here is how can we help students develop more expert-like frameworks on which to construct new knowledge. We argue that the typical structure of introductory college-level chemistry courses does not support the development of a robust, useful knowledge base, thus setting students up for problems in later courses. Introductory college-level courses are typically designed as surveys of the discipline and are often denoted as such in course catalogs. Presumably the intent behind introducing students to college-level work by surveying the discipline is to offer beginning students the needed exposure to a wide range of ideas and topics, either as preparation for further studies in that discipline or other related disciplines or, if the student does not intend further study, to give them an idea of what the discipline entails. Unfortunately, we now know that this approach to building knowledge is supported by neither evidence nor learning theories. That is, a curriculum that is “a mile wide and an inch deep” provides students with a huge amount of material without appropriate structural support to allow connections to be made between the facts or skills that are presented, enabling students to make sense of them.2 These surveys of the discipline make it very difficult for students to develop a coherent framework on which to build their © XXXX American Chemical Society and Division of Chemical Education, Inc.

knowledge, because of the (necessarily) fragmentary nature of a course that is pulled together in this way. As a result, students often leave these courses with little usable knowledge that is transferrable to subsequent studies or an understanding of the organization of the discipline. This means that a vast majority of students, who do not study chemistry beyond the gateway courses, will never have another opportunity to build a coherent understanding. It also means that many students who go on to subsequent courses are often not prepared to use what knowledge they have in a new situation. While there have been many attempts to reform general chemistry,3−8 much of the more recent reform effort has been focused on introducing active engagement techniques.9−11 However, calls for depth over breadth have generally not been heeded. Indeed, over the years most general chemistry textbooks have expanded to include more topics and skills, and little has been omitted, resulting in an explosion of the ideas addressed in a typical textbook. For example, since the first edition of General Chemistry by Brown in 1968, the number of pages has more than doubled, and the number of figures has tripled.12 There is evidence that depth produces better outcomes than breadth in high school studies.13 However, this approach has been slow to arrive at college-level chemistry courses, despite the fact that there is ample evidence that students have great difficulty understanding much of the chemistry taught: the Received: November 21, 2016 Revised: February 15, 2017

A

DOI: 10.1021/acs.jchemed.6b00900 J. Chem. Educ. XXXX, XXX, XXX−XXX

Journal of Chemical Education

Article

Table 1. Comparison of the Big Ideas across Current Projects

overarching ideas.20 Core ideas are ideas that are central to the discipline and provide the underlying support for a wide range of concepts across the discipline. The most ambitious of the projects that revolve around core ideas is the approach developed in the National Research Council’s report titled A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas20 (referred to as the Framework in this paper). The Framework lays out a vision for how science education can be designed on the basis of our current understanding of learning in the sciences. Disciplinary core ideas (DCIs) that span the K−12 years are identified for life sciences; earth and space sciences; physical sciences; and engineering, technology, and applications of science. Those that are most applicable to chemistry are shown in Table 1. The Framework is the basis for the Next Generation Science Standards (NGSS),21 which have been adopted by many states and are guiding standards development in many more states. What is interesting and notable about these standards is that they are not parsed out into smaller units of fragmentary information and that they span multiple years. In contrast, many state standards and other reform efforts often present much finer-grained lists of knowledge, concepts, and skills that students should learn at each grade or grade band. The approach taken in the Framework and NGSS combines the DCIs with Scientific and Engineering Practices (how knowledge is used), and Crosscutting Concepts (ideas that cross disciplines) in ways that are designed to help students develop a connected, coherent understanding. The move toward characterizing overarching ideas is also present in several chemistry-specific projects, which are compared with DCIs from the Framework and with each other

research literature is replete with descriptions of difficulties that students have in these introductory courses.14 Literally hundreds of misconceptions have been reported,15,16 yet there are few reports of interventions that have been shown to improve the situation in a measurable and lasting way.14 For example, the idea that bonds release energy when they are broken is problematic and highly resistant to instruction.17,18 This is almost certainly due to the fragmented nature of how ideas about energy are taught across different disciplines, and even within chemistry itself.19 We argue here that we must help students develop more expert-like knowledge structures and provide an approach that is supported by research and evidence. While we are not expecting that general chemistry students become experts in chemistry over the course of two semesters, we propose that what they do learn should be part of a coherent framework. Students should be provided with opportunities to build a network of ideas that are connected and contextualized such that if students do need to call on the ideas that they have been taught at a subsequent time, they will have a better chance of recalling and being able to use that knowledge.



FOCUSING ON CORE IDEAS

If the typical introductory survey course is neither pedagogically appropriate nor effective, how then can we approach the development of introductory (and for that matter advanced) curricular structures to provide students with the kinds of experiences that would help them build a more expert-like framework? An approach that is gaining momentum across all levels of STEM education is to identify the “core ideas” of the discipline and to structure the curriculum around these B

DOI: 10.1021/acs.jchemed.6b00900 J. Chem. Educ. XXXX, XXX, XXX−XXX

Journal of Chemical Education

Article

in level 4. So, for example, it is suggested that one way to assess an aspect of the big idea of bonding is that bond dissociation enthalpies can be used to calculate reaction enthalpy changes. For experts, the relationship between this type of calculation and the overarching idea that atoms interact to form stable bonds is obvious, but for most students it is not. It is quite likely that students can do these kinds of calculations without actually understanding why the calculation can be done or indeed that bond breaking requires an input of energy (level 2) or that atoms interact via electrostatic forces to form chemical bonds (level 1). As discussed earlier, this is a highly problematic area for many students.17,18 Certainly it is important that students practice skills and are able to recall important facts and ideas with facility and fluidity, but if these fragments cannot be constructed into a coherent framework, then this knowledge will not be useful (except to answer examination questions that address fragmentary knowledge). As noted earlier, the Framework and the NGSS provide a radical new vision for how to construct robust and useful knowledge.20,21 While the vision may seem similar to a “big” ideas approach, it differs both in the ways that the core ideas are connected over time and across disciplines and in the level at which the students’ knowledge is assessed. As discussed below, the expectation that student understanding be assessed at the level of the core ideas rather than the fragments provides guidance for curriculum designers.

in Table 1. These include the Advanced Placement (AP) Chemistry redesign project which describes six “big ideas”22,27 and the College Board Standards for College Success25 that developed three “big ideas”-based standards for high school chemistry. At the college level the American Chemical Society (ACS) Examinations Institute, in a process that involved a large number of faculty building consensus, identified 10 “anchoring concepts” (big ideas) for undergraduate chemistry.28 We note here that the ACS curriculum map contains two anchoring concepts (IX. Experiments, Measurement, and Data and X. Visualization) which we do not include in Table 1 because they are different in that they refer to the use of knowledge, rather than the knowledge itself. Similarly, we do not include the recent alternative approach proposed by Talanquer,29 which includes actions, such as substance characterization and structure determination. As we will discuss later, our approach relies on the vision put forth in the Framework, in which the core ideas are blended with Scientific and Engineering Practices to provide expectations about what a student should know and be able to do with their knowledge.20 These approaches to describing big ideas or anchoring concepts have similarities and differences. Each identifies a set of overarching ideas, typically followed by a hierarchy of ideas that fall underneath the “big” idea. For example, the ACS curriculum map,28 which is certainly the most extensive description we have of the possible content of a college general chemistry course,24 identifies four levels: level 1 anchoring concepts (big ideas), level 2 enduring understandings, level 3 subdisciplinary articulation, and level 4 content details (fine-grained). For example, Box 1 shows examples from levels 1−4 for the anchoring concept “Bonding”.23,24



DEVELOPING CORE IDEAS FOR GENERAL CHEMISTRY As part of an effort to transform the gateway chemistry, biology, and physics courses at Michigan State University (MSU) by focusing on assessment of student learning,30 we adapted the approach described in the Framework which involves identifying the core ideas in chemistry that underlie much of what we expect students to learn in general chemistry (and a great deal of what we expect students to learn in upper-level courses as well). An overview and brief description of four core ideas,26 which emerged from extensive discussions with MSU faculty, are shown in Box 2.

Box 1. Anchoring Concept Levels 1−4 for Bonding23,24 Anchoring Concept II. Bonding: Atoms interact via electrostatic forces to form chemical bonds. Enduring Understanding D. To break a chemical bond requires an input of energy. Subdisciplinary Articulation 1. The energy required to break a chemical bond is the bond dissociation energy. Content Detail a. Bond dissociation energy is useful at the level of individual molecules; for calculations on macroscopic quantities, the value used is the bond dissociation enthalpy. Content Detail b. Bond dissociation enthalpies can be used to estimate the change in enthalpy for a reaction.



CORE IDEAS, TOPICS AND FRAGMENTS The obvious question here is how this approach differs from the prior projects that have delineated big/core ideas or anchoring concepts. Clearly, our core ideas do align with the other national initiatives,22−25 but we also understand that others may prefer to define their own ideas. Here we make the argument that the importance of our approach lies in how core ideas are used to construct the curriculum and the accompanying assessment items. Most general chemistry curricula focus on a set of topics, which are often treated as separate chapters in texts. For example, “Thermochemistry” and “Phases and Phase Changes” address different aspects of some of the same core ideas (e.g., Energy and Electrostatic and Bonding Interactions) yet are found separated by several chapters in most texts. As noted earlier, the assessment items are often at an even smaller grain size: the fragmentary level, for example, calculation of reaction enthalpies or bond dissociation energies using Hess’ law or calculation of enthalpies of vaporization using the Clausius−Clapeyron equation. The problem with this approach is that it becomes very difficult for students to connect the fragments to the larger core ideas since students can answer these questions by learning a

What makes the College Board, AP, and ACS approaches somewhat different from the Framework and NGSS is that they all start with the “overarching ideas” and then drill down to the individual knowledge fragments. However, this may lead to an inadvertent tendency to assess these individual fragments, rather than helping students understand how these fragments contribute to the overarching ideas of the discipline. For example, the ACS curriculum map (Box 1) provides a very detailed overview of current general chemistry content.23,24 It is telling, however, that the detail about assessments (i.e., what students should know and be able to do) is found at level 4 (i.e., Content Detail statements a and b in Box 1). Indeed, the guidance that is given for the kinds of assessments and the ways they can be designed is typically included C

DOI: 10.1021/acs.jchemed.6b00900 J. Chem. Educ. XXXX, XXX, XXX−XXX

Journal of Chemical Education

Article

other.31,32 Determining the types of IMFs then connects to electrostatic and bonding interactions because students must be able to identify which interactions are broken or formed during a phase change. For most molecular substances this means that intermolecular forces (noncovalent interactions) are involved, not covalent bonds, yet the well-documented misconception33,34 that boiling water results in hydrogen and oxygen atoms being formed stems from a misunderstanding of this process.35,36 Phase change also requires a connection to energy (at both the macroscopic and atomic/molecular levels). Energy transfer from system to surroundings for the change from gas to liquid to solid can only be explained by formation of new interactions in the system, which release energy, and vice versa for the change from solid to liquid to gas. At the atomic/ molecular level, temperature is a measure of the average kinetic energy of the particles in a system. Phase changes from gas to liquid to solid occur as the kinetic energy of the particles decreases until the kinetic energy is not sufficient to overcome the attractive IMFs when particles collide. Phase changes from solid to liquid to gas occur when the particles in the system have sufficient kinetic energy to overcome attractive intermolecular forces, first to allow the particles to move relative to each other in the transition from solid to liquid and eventually to escape from the liquid to the gas phase. The transfer of energy within the system and between the system and surroundings is mediated by collisions that cause changes in the kinetic energy of the particles. Similarly, the core idea of change and stability in chemical systems may be invoked if students are expected to understand why the temperature does not change at the phase change point, and why, for example, freezing occurs even though the entropy change of the system is negative. Kinetics is listed as a separate big idea in both the ACS and AP curriculum maps; however, we believe that kinetics is more appropriately classified as a topic which can be better understood by being situated in the four core ideas. Obviously kinetics can be linked to the change and stability in chemical systems core idea, since it is essentially the study of change in chemistry. However, for many traditional general chemistry courses most of the activity is taken up not with ideas about how reactions take place and what causes chemical change, but rather with calculations involving time and concentration data or analyzing initial rates data to determine kinetic rate laws. What is often lost in the mathematical introduction are the underlying foundational ideas along with the actual reason why one might want to determine rate laws and why some reactions proceed at faster rates than others. For example, the topic kinetics is connected to energy changes at the molecular level, because the rate of reaction depends upon the activation energy, which in turn is connected to the structure of the substances undergoing reaction and the details of how they interact, i.e., the mechanism of the reaction. For example, Brønsted−Lowry acid−base reactions are faster than nucleophilic substitution reactions because of the types of bonds and interactions present before and during the reaction: transferring a proton has a much lower activation energy than breaking a bond to carbon. Ideally, our goal would be to connect every major topic in general chemistry (and perhaps in every chemistry course) to the core ideas, to support student development of a more robust framework on which to build future knowledge. Table 2 provides more examples of common topics and how they can be supported by the core ideas.

Box 2. The Core Ideas in Chemistry as Delineated by the MSU Project I. Electrostatic and Bonding Interactions: Attractive and repulsive electrostatic forces govern the interactions between the electrons and nuclei in atoms and the noncovalent and bonding (covalent and ionic) interactions between atoms and molecules. The strength of these forces depends on the magnitude of the charges involved and the distances between them. II. Atomic/Molecular Structure and Properties: The macroscopic physical and chemical properties of a substance are determined by the three-dimensional structure, the distribution of electron density, and the nature and extent of the noncovalent interactions between particles. III. Energy: Energy changes are either the cause or the consequence of change in chemical systems, which can be considered on different scales and can be accounted for by conservation of the total energy of the system of interest and the surroundings. A. Macroscopic: Changes in phase and reactions of collections of atoms and/or molecules are accompanied by energy changes that result from energy changes on the atomic/molecular scale. B. Atomic/Molecular: Kinetic and potential energy changes occur when atoms and molecules interact. Energy is released to the surroundings when bonds or attractive noncovalent interactions form, and conversely energy is required to break bonds or noncovalent interactions. C. Quantum Mechanical Energy Levels and Changes: Energy levels are quantized in atoms and molecules resulting in discrete energies for transitions between energy levels. This is a direct consequence of the wave−particle duality of electrons and other subatomic particles. IV. Change and Stability in Chemical Systems: Energy and entropy changes, the rates of competing processes, and the balance between opposing forces govern the fate of chemical systems. procedure without needing to connect them to the core ideas. While it is obviously necessary to retain recognizable topics, we propose that these topics must be clearly and continuously connected back to the core ideas of the discipline, both during learning and in the formative and summative assessment items that are used. In Table 2, we provide examples of common topics and possible ways they can be connected to the core ideas. For example, the topic of phase changes is a chemical phenomenon that can be linked to all of our four core ideas. The connection to structure and properties is perhaps the most obvious since the structure of the substance determines the properties, which include the phase change temperature. However, there are many more connections that students must make before they can connect structure with macroscopic properties: They must be able to use the chemical structure to determine molecular-level properties, such as molecular shape and polarity, and from the polarity and arrangement of the atoms within the molecule they must also be able to determine what types of intermolecular forces (IMFs) are present and how the interacting molecules are oriented with respect to each D

DOI: 10.1021/acs.jchemed.6b00900 J. Chem. Educ. XXXX, XXX, XXX−XXX

Journal of Chemical Education

Article

Table 2. Examples of the Relationship between Core Ideas and Chemistry Topics Sample Topics (Chapter Headings) Periodic Trends

Solutions

Phases and Phase Changes

Kinetics

Thermochemistry

Relationship to Core ideas Atomic/Molecular Structure and Properties: Trends that repeat across rows and down columns arise from the atomic structure. Electrostatic and Bonding Interactions: Electrostatic interactions (that give rise to effective nuclear charge) between subatomic particles explain most periodic trends. Energy: Quantum: Patterns in ionization energies arise from the quantized nature of the energy levels. Shielding by core electrons determines the effective nuclear charge experienced by valence electrons and results from the relationship between the quantized energy levels in atoms and the associated shell structure. Change and Stability in Chemical Systems: Balance between attractive and repulsive forces determines the size of atoms. Atomic/Molecular Structure and Properties: Solubility of a substance depends upon the molecular level structure of both solute and solvent. Electrostatic and Bonding Interactions: Interactions between solvent and solute partly determine the solubility. Energy: Macroscopic: Temperature changes that take place when a substance dissolves depend on the energy required to overcome interactions and energy released when new interactions are formed. Change and Stability in Chemical Systems: Solubility of a substance depends on the total entropy change when a substance dissolves. Atomic/Molecular Structure and Properties: Melting/boiling point of a substance depends on its molecular-level structure. Electrostatic and Bonding Interactions: Types and strengths of interactions at the molecular level influence melting/ boiling points. Energy: Macroscopic: Energy changes associated with phase changes are determined by the types and strengths of interactions. Change and Stability in Chemical Systems: Phase change temperatures depend upon the energy transfer between system and surroundings and the corresponding entropy changes. Atomic/Molecular Structure and Properties: Rates of chemical reactions depend on the structures of the reacting species and the probability of the reactants being properly oriented in a collision. The mechanism for the reaction also depends on the molecular structure. Electrostatic and Bonding Interactions: Rates of chemical reactions depend on the strengths of the interactions between the reacting species and the strengths of the bonds within them. Energy: Molecular and Macroscopic: Rates of chemical reactions depend on the activation energy (which in turn depends on the structure and interactions) and on the kinetic energy of the colliding reactant molecules. Change and Stability in Chemical Systems: Kinetics is the study of how and why chemical change occurs. Competing rates of forward and reverse reactions control the extent of a reaction and when balanced equilibrium is reached. Atomic/Molecular Structure and Properties: Some bonds and interactions are broken and new ones formed in a chemical reaction. Electrostatic and Bonding Interactions: Types and strengths of bonds and interactions depend on the structure and polarity of the molecules involved. The strength of the interactions can be predicted from electrostatic considerations. Energy: Molecular and Macroscopic: Energy change in a chemical reaction is a balance between the energy required to break bonds and interactions, and the energy released when new bonds and interactions are formed. Change and Stability in Chemical Systems: Whether a chemical reaction occurs or not depends on the total entropy change, which can be determined from a consideration of enthalpy and entropy changes of the system.

Figure 1. (A) One approach to construction of assessments involves breaking down core ideas, such as those illustrated for the anchoring concepts in the ACS curriculum map, into progressively finer levels of detail which generally results in assessment at the finest level of detail (content details in the ACS curriculum map). (B) As an alternative, we propose an approach that builds assessments around core ideas to require students to draw on and connect finer-grained ideas, often from multiple levels. E

DOI: 10.1021/acs.jchemed.6b00900 J. Chem. Educ. XXXX, XXX, XXX−XXX

Journal of Chemical Education



Article

DESIGNING ASSESSMENTS THAT CONNECT TO THE CORE IDEAS A reasonable reader may now be asserting that these connections are made in most general chemistry texts. Certainly, as experts, we do see these connections, but as noted earlier, there is ample evidence that students do not. We argue that part of the problem lies with the nature of the assessments that are in common use, which often target individual skills or fragmentary knowledge, for example, the knowledge at level 4 on the ACS curriculum map as previously discussed. The nature of the assessment items in a course sends a strong message to students about what is important. If all students are expected to do is to perform rote calculations (even very cognitively demanding ones) or provide fragments of information or answer questions that do not require evidence of the reasoning required to provide a prediction,32 they cannot be expected to construct an expert-like framework. Certainly it is possible that these fragments can be integrated into a deeper understanding at a later date; however, we argue that for most students this will not be achieved until we design formative and summative assessment items that require students to make connections to core ideas. Constructing these kinds of assessments can be quite complex and will be extensively discussed in a future paper. However, our approach aligns with the NRC report “Knowing What Students Know”37 in that we approach assessment as an evidentiary argument. That is, a meaningful assessment must be designed to elicit convincing evidence from students about how they understand the particular construct. This means that we must use prompts that require students to use their knowledge rather than merely restating that knowledge. One approach to the development of such items is to adopt the Scientific and Engineering Practices that are presented in the Framework.20 These practices describe the ways that scientists and engineers work with knowledge: for example, developing and using models as well as constructing explanations and arguments are practices that require students to provide reasoning and communicate how they understand these ideas. Indeed, it is almost impossible to construct tasks that require students to make connections to core ideas without using these practices. The difference between our approach and the more traditional approach is presented in Figure 1. Rather than assess at the fragmentary knowledge level, we propose that assessment items must be explicitly connected back to the core ideas. As an example, previously we discussed the commonly assessed task of calculating reaction enthalpies from bond dissociation energies. Students often learn a procedure that allows them to successfully calculate reaction enthalpies without explicit consideration of the fact that formation of bonds releases energy to the surroundings and breaking bonds requires an input of energy from the surroundings. Box 3 provides an example of how such a question could be revised to elicit evidence of student engagement with core ideas. Another example comes from a consideration of what students must be able to do to provide evidence that they understand why methanol has a higher boiling point than ethane even though the two have similar molecular weights. In fact, many students can answer the more traditional multiple choice question “which has a higher boiling point?”, and will choose “because it can hydrogen bond” as the reason. However, as discussed earlier35,36 we have shown that the majority of students tend to draw hydrogen bonds as the covalent bond

Box 3. Example of a Cluster of Assessment Questions Focused on the Core Ideas of Energy (Macroscopic), Energy (Microscopic), and Electrostatic and Bonding Interactions a. Calculate the enthalpy change for this reaction using the table of bond energies provided: CH3CHCH 2 + H 2O → CH3CH 2CH 2OH

b. What does your result from part a tell you about the flow of energy between the system and surroundings in this reaction? c. Draw an energy diagram showing the relative energies of the reactants and products. d. Discuss the strength of interactions and the processes responsible for the energy changes between the reactants and product using your answer to part c. between the O and H (which makes the idea that bonds break when substances boil somewhat more understandable). To redesign these questions to connect to core ideas we can scaffold the question as shown in Box 4 so that students would Box 4. Example Assessment Question Focused on the Core Ideas of Atomic/Molecular Structure and Properties, Energy (Molecular), and Electrostatic and Bonding Interactions a. Draw the Lewis structures of C2H6, CH3OH. b. Draw three molecules of each substance and show where the strongest intermolecular forces are located and identify these forces. c. Which substance do you think has the highest boiling point? (This is your claim.) d. What factors affect the substance’s’ boiling point? (This is your evidence.) e. How do these factors affect the boiling point? (This is part of your reasoning.) f. Why do these factors affect the boiling point? (This is also part of your reasoning.) (i) draw several methanol and ethane molecules; (ii) indicate where the strongest intermolecular forces are and identify them; and (iii) choose which one has a higher boiling point and explain why using an argumentation framework of claim, evidence, and reasoning (or explain using the core ideas of forces and energy what happens when methanol and ethane boil). Both of the examples provided are constructed response items, and many would argue that such questions are impractical for large-enrollment general chemistry courses. Similar questions have been used in a general chemistry course with an enrollment of 2500 students in a semester and have been graded successfully by graduate teaching assistants and undergraduate learning assistants using a rubric. A future paper on designing assessments will address how such questions can be converted to a selected response format. While our goal is not to direct instructional approaches, we believe that students must also be supported in making these connections during learning activities by actively engaging with the Scientific and Engineering Practices. One further note: as the NGSS have been adopted across the nation, supporting F

DOI: 10.1021/acs.jchemed.6b00900 J. Chem. Educ. XXXX, XXX, XXX−XXX

Journal of Chemical Education

Article

(8) Atkins, P. Chemistry: The Great Ideas. Pure Appl. Chem. 1999, 71 (6), 927−929. (9) Freeman, S.; Eddy, S. L.; McDonough, M.; Smith, M. K.; Okoroafor, N.; Jordt, H.; Wenderoth, M. P. Active Learning Increases Student Performance in Science, Engineering, and Mathematics. Proc. Natl. Acad. Sci. U. S. A. 2014, 111, 8410−8415. (10) Process Oriented Guided Inquiry Learning (POGIL); Moog, R. S., Spencer, J. N., Eds.; American Chemical Society: Washington, DC, 2008. (11) Gafney, L.; Varma-Nelson, P. Peer-Led Team Learning: Evaluation, Dissemination, and Institutionalization of a College Level Initiative; Cohen, K., Ed.; Innovations in Science Education and Technology; Springer: Weston, MA, 2008. (12) Hamilton, T. M. Textbook Inflation: Thirty-Five Years of Brown’s General Chemistry Textbook. Chem. Educ. Res. Pract. 2006, 7 (1), 46−48. (13) Schwartz, M. S.; Sadler, P. M.; Sonnert, G.; Tai, R. H. Depth versus Breadth: How Content Coverage in High School Science Courses Relates to Later Success in College Science Coursework. Sci. Educ. 2009, 93 (5), 798−826. (14) National Research Council. Discipline-Based Education Research: Understanding and Improving Learning in Undergraduate Science and Engineering; Singer, S. R, Nielson, N. R., Schweingruber, H. A., Eds.; National Academies Press: Washington, DC, 2012. (15) Barker, V. Beyond Appearances: Students’ Misconceptions about Basic Chemical Ideas; Royal Society of Chemistry: London, 2000; p 78. (16) Taber, K. S. Chemical Misconceptions: Prevention, Diagnosis and Cure; Royal Society of Chemistry: London, 2002; Vol. 1. (17) Boo, H. K. Students’ Understandings of Chemical Bonds and the Energetics of Chemical Reactions. J. Res. Sci. Teach. 1998, 35, 569−581. (18) Teichert, M. A.; Stacy, A. M. Promoting Understanding of Chemical Bonding and Spontaneity through Student Explanation and Integration of Ideas. J. Res. Sci. Teach. 2002, 39, 464−496. (19) Cooper, M. M.; Klymkowsky, M. W. The Trouble with Chemical Energy: Why Understanding Bond Energies Requires an Interdisciplinary Systems Approach. CBE Life Sci. Educ. 2013, 12, 306−312. (20) National Research Council. A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas; National Academies Press: Washington, DC, 2012. (21) National Research Council. Next Generation Science Standards: For States, By States; The National Academies Press: Washington, DC, 2013. (22) College Board. Advances in AP: AP Chemistry. https:// advancesinap.collegeboard.org/stem/chemistry (accessed Feb 2017). (23) Holme, T.; Luxford, C.; Murphy, K. Updating the General Chemistry Anchoring Concepts Content Map. J. Chem. Educ. 2015, 92, 1115−1116. (24) Holme, T.; Murphy, K. The ACS Exams Institute Undergraduate Chemistry Anchoring Concepts Content Map I: General Chemistry. J. Chem. Educ. 2012, 89, 721−723. (25) College Board. College Board Standards for College Success: Science. http://apcentral.collegeboard.com/apc/public/repository/ cbscs-science-standards-2009.pdf (accessed Feb 2017). (26) Laverty, J. T.; Underwood, S. M.; Matz, R. L.; Posey, L. A.; Carmel, J. H.; Caballero, M. D.; Fata-Hartley, C. L.; Ebert-May, D.; Jardeleza, S. E.; Cooper, M. M. Characterizing College Science Assessments: The Three-Dimensional Learning Assessment Protocol. PLoS One 2016, 11, e0162333. (27) Rushton, G. T. Introducing the Journal of Chemical Education’s “Special Issue: Advanced Placement (AP) Chemistry. J. Chem. Educ. 2014, 91 (9), 1273−1275. (28) Murphy, K.; Holme, T.; Zenisky, A.; Caruthers, H.; Knaus, K. Building the ACS Exams Anchoring Concept Content Map for Undergraduate Chemistry. J. Chem. Educ. 2012, 89 (6), 715−720. (29) Talanquer, V. Central Ideas in Chemistry: An Alternative Perspective. J. Chem. Educ. 2016, 93 (1), 3−8.

materials have emerged in which the disciplinary core ideas of the framework have been unpacked.38,39 Here we are suggesting a somewhat different approach in that it is the topics that should be unpacked to connect them to the core ideas.



CONCLUSIONS Structuring curricula and concomitant assessment items around core ideas instead of topics can help students build a more expert-like framework of knowledge with which they can predict and explain chemical phenomena. Returning to these core ideas as often as possible means that the connections to these ideas are strengthened, helping students to make sense of what they are learning. If we treat chemistry as a set of topics that are separate and, in many cases, can be taught in any order, it is unlikely that students will be able to construct a coherent understanding of chemistry.



AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. ORCID

Melanie M. Cooper: 0000-0002-7050-8649 Notes

Any opinions, findings, conclusions, or recommendations expressed here are those of the authors and do not necessarily reflect the views of the National Science Foundation. The authors declare no competing financial interest.



ACKNOWLEDGMENTS This work was supported in part by the Association of American Universities’ (AAU) Undergraduate STEM Education Initiative, funded by the Helmsley Charitable Trust, and by the National Science Foundation under DUE 0816692 (1359818). We would also like to acknowledge the chemistry faculty at Michigan State University who contributed to the development of our core ideas. In addition, we would like to acknowledge the AAU project team at Michigan State University: Marcos D. Caballero, Justin H. Carmel, Diane Ebert-May, Cori L. Fata-Hartley, Sarah E. Jardeleza, Joseph S. Krajcik, James T. Laverty, and Rebecca L. Matz.



REFERENCES

(1) National Research Council. How People Learn: Brain, Mind, Experience, and School; National Academies Press: Washington, DC, 1999. (2) Schmidt, W. H.; McKnight, C. C.; Raizen, S. A Splintered Vision: An Investigation of US Science and Mathematics Education; Springer Science & Business Media: New York, 2002. (3) Anthony, S.; Mernitz, H.; Spencer, B.; Gutwill, J.; Kegley, S. E.; Molinaro, M. The ChemLinks and ModularCHEM Consortia: Using Active and Context-Based Learning to Teach Students How Chemistry Is Actually Done. J. Chem. Educ. 1998, 75 (3), 322−324. (4) American Chemical Society. Chemistry, A General Chemistry Project of the American Chemical Society; WH Freeman: New York, 2004. (5) Talanquer, V.; Pollard, J. Let’s Teach How We Think Instead of What We Know. Chem. Educ. Res. Pract. 2010, 11 (2), 74−83. (6) Ellis, A. B.; Gerselbracht, M. J.; Johnson, B. J.; Lisensky, G. C.; Robinson, W. R. Teaching General Chemistry: A Materials Science Companion; American Chemical Society: Washington, DC, 1993. (7) Gillespie, R. J. The Great Ideas of Chemistry. J. Chem. Educ. 1997, 74 (7), 862−864. G

DOI: 10.1021/acs.jchemed.6b00900 J. Chem. Educ. XXXX, XXX, XXX−XXX

Journal of Chemical Education

Article

(30) Cooper, M. M.; Caballero, M. D.; Ebert-May, D.; Fata-Hartley, C. L.; Jardeleza, S. E.; Krajcik, J. S.; Laverty, J. T.; Matz, R. L.; Posey, L. A.; Underwood, S. M. Challenge Faculty to Transform STEM Learning. Science 2015, 350 (6258), 281−282. (31) Cooper, M. M.; Underwood, S. M.; Hilley, C. Z. Development and Validation of the Implicit Information from Lewis Structures Instrument (IILSI): Do Students Connect Structures with Properties? Chem. Educ. Res. Pract. 2012, 13, 195−200. (32) Cooper, M. M.; Corley, L. M.; Underwood, S. M. An Investigation of College Chemistry Students’ Understanding of Structure−property Relationships. J. Res. Sci. Teach. 2013, 50, 699− 721. (33) Johnson, P. Children’s Understanding of Changes of State Involving the Gas State, Part 1: Boiling Water and the Particle Theory. Int. J. Sci. Educ. 1998, 20, 567−583. (34) Bodner, G. M. I Have Found You an Argument: The Conceptual Knowledge of Beginning Chemistry Graduate Students. J. Chem. Educ. 1991, 68 (5), 385−388. (35) Cooper, M. M.; Williams, L. C.; Underwood, S. M. Student Understanding of Intermolecular Forces: A Multimodal Study. J. Chem. Educ. 2015, 92 (8), 1288−1298. (36) Williams, L. C.; Underwood, S. M.; Klymkowsky, M. W.; Cooper, M. M. Are Noncovalent Interactions an Achilles Heel in Chemistry Education? A Comparison of Instructional Approaches. J. Chem. Educ. 2015, 92, 1979−1987. (37) National Research Council. Knowing What Students Know: The Science and Design of Educational Assessment; Pellegrino, J. W., Chudowsky, N., Glaser, R., Eds.; National Academies Press: Washington, DC, 2001. (38) Krajcik, J.; Codere, S.; Dahsah, C.; Bayer, R.; Mun, K. Planning Instruction to Meet the Intent of the Next Generation Science Standards. J. Sci. Teach. Educ. 2014, 25 (2), 157−175. (39) Evidence Statements | Next Generation Science Standards. http:// www.nextgenscience.org/evidence-statements (accessed Jan 14, 2017).

H

DOI: 10.1021/acs.jchemed.6b00900 J. Chem. Educ. XXXX, XXX, XXX−XXX