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Jun 11, 2013 - The Next Generation Science Standards (NGSS) describe what all students should know about science and engineering, and be able to do by...
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Chemistry and the Next Generation Science Standards Melanie M. Cooper* Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States ABSTRACT: The Next Generation Science Standards (NGSS) describe what all students should know about science and engineering, and be able to do by the time they leave high school. The NGSS are based on learning progressions of core ideas in the discipline, crosscutting concepts across disciplines, and the practices that will allow students to use their disciplinary knowledge in meaningful ways. As states adopt the NGSS, significant changes will be required in all areas of science education, including the development of new curricula and assessments. Support for both pre- and inservice teachers will be crucial, and perhaps less obviously, so will changes in the way chemistry is taught at the college level. The Next Generation Science Standards logo is ©Copyright 2013 and reprinted here with permission of Achieve, Inc., with all rights reserved. KEYWORDS: High School/Introductory Chemistry, Elementary/Middle School Science, General Public, First-Year Undergraduate/General

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cause and effect, energy, systems, scale, structure and function, and stability and change are important concepts that appear in all science disciplines. We must help students make these connections to help them construct a coherent understanding of science concepts. Science practices are essentially the disaggregated components of inquiry. The word “inquiry” means different things to different people; this makes it somewhat difficult to assess. Instead, the NRC defined a set of Science and Engineering Practices that are each more clearly defined, and therefore lend themselves better to appropriate assessments. These practices go beyond skills because they also involve knowledge that is specific to each practice. Practices are the ways that scientists understand and explore the natural world, and include activities that are quite familiar to chemists, such as: planning and monitoring experiments; analyzing and interpreting data; using mathematical thinking; developing and using models; engaging in argument from evidence; and developing explanations. However, an important aspect is the active nature of the science practiceslearners engage in argument, and construct and revise models based on evidence. The standards themselves take the form of “performance expectations” in which the three strands from the framework are tightly woven, rather than separate content and inquiry standards. That is, each performance expectation links disciplinary knowledge, a science practice, and a crosscutting concept. The important point to note here is that these performance expectations guide the development of assessments: when a standard encompasses all three strands, then so must the assessment. It will no longer be possible to meet a standard solely by recall of factual knowledge.

n April 2013, the Next Generation Science Standards (NGSS) were released.1 They build on the (now almost 20year-old) AAAS Benchmarks for Science Literacy,2 and National Science Education Standards,3 in that they provide guidance about what all students should know and be able to do with that scientific knowledge. The NGSS are designed to bring insights from newer research on how students learn science4 into curricular design and delivery, and to provide a standards structure that emphasizes a deeper understanding of a smaller, yet more central number of core concepts. In a world where facts are just a click away, it is the context of the knowledge and the ability to use it that will become ever more important. The NGSS are based on the NRC Framework for Science Education5 that is composed of three strands: disciplinary core ideas, crosscutting concepts, and science (and engineering) practices. Disciplinary core ideas (DCIs) are significant ideas of broad importance to the discipline; they have explanatory power, are generative of more specialized ideas, and can be developed over time from K−12 (and beyond). The DCIs in the framework are necessarily of a fairly large grain size. For example, the first physical science core ideaPS-1, Matter and its Interactionsis guided by the question “How can one explain the structure, properties, and interactions of matter?” The development of PS-1 begins in the early elementary years with the idea that “matter exists as difference substances as exhibited by their observable properties”5 and progresses through high school where “the sub-atomic model and interactions between electric charges can be used to explain interactions of matter”.5 This research-based longitudinal and developmental elaboration of a core concept is often termed a learning progression.6 As their name implies, the crosscutting concepts are those ideas that reach across disciplines to tie them together. Patterns, © 2013 American Chemical Society and Division of Chemical Education, Inc.

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dx.doi.org/10.1021/ed400284c | J. Chem. Educ. 2013, 90, 679−680

Journal of Chemical Education

Editorial

teach our introductory chemistry courses in a traditional way, using lectures, cookbook laboratories, and multiple-choice testing, future teachers will not develop expertise in asking questions, developing models, or arguing from evidence. It is important for those of us who teach these courses to reflect on the impact we may have on future teachers, and frankly on future scientists and engineers. In the long run it is not what students know that is important, but what students do with that knowledge. The adoption of the NGSS could bring about significant improvements at all levels of chemistry education from K−20, but only if we as educators “buy-in” to the approach. It may mean that we have to make changes in how and what we teach, yet the result will be students who actually understand and can use their chemical knowledge.

For example, HS-PS1-4 (high school, physical sciences core idea 1, performance expectation 4) is: “Develop a model to illustrate that the release or absorption of energy f rom a chemical reaction system depends upon the changes in total bond energy.”5 This standard is cross-referenced to the science practice of constructing models, the crosscutting concepts of matter and energy, and the disciplinary core idea “Stable forms of matter are those in which the electric and magnetic field energy is minimized”.5 The performance expectation is designed to help teachers, curriculum developers, and assessment developers address the highly problematic area of “chemical energy”a concept that is well documented as an area of major conceptual difficulty for many students. The clarification statement reads in part:5 Emphasis is on the idea that a chemical reaction is a system that affects the energy change. Examples of models could include molecular-level drawings and diagrams of reactions, graphs showing the relative energies of reactants and products, and representations showing energy is conserved. Now, contrast this activity to a typical activity on chemical energy in which students may perform calculations using an equation (e.g., ΔH = Σ bond energy bonds broken − Σ bond energy bonds formed). In the calculation, students must only insert numbers into the formula; the origin of the formula is not apparent, nor is the reason for the negative sign. The NGSS performance expectation is intended to elicit the students’ mechanistic understanding of what happens at the molecular level when bonds break and form, and the energy changes associated with this process. This approach to the energy changes that take place when atoms and molecules interact is designed to help students understand that there is a spectrum of interactions, from intermolecular forces to bonds, and that these interactions are manifestations of the same phenomena to different degrees. Similarly, HS-PS-1-5 steers away from the conventional treatment of reaction rates to a molecular-level understanding of how and why changing the temperature or concentration affects rate: “Apply scientif ic principles and evidence to provide an explanation about the effects of changing the temperature or concentration of the reacting particles on the rate at which a reaction occurs.”5 Note that the practice here is “explanation”, using scientific principles and evidence (which may be provided, or the students may produce). Again the emphasis here is on what happens at the molecular level when molecules interact, and why changing the concentration or the temperature affects the rate of a reaction. The most obvious ramifications of the wide-scale adoption of the NGSS are that significant changes will be required in almost all areas of science education. The NGSS are merely the end points, describing what all students should know and be able to do at the end of grade level for K−5, and at the end of grade band for 6−8, and 9−12. How students get to these end points will require the development of new curriculum materials, new assessments, and extensive support for teachers, both those already in the field and those who are enrolled in teacher education programs. However, what is not quite so obvious is that the NGSS should also affect the science courses in which future teachers learn their disciplinary content. Teachers who learn chemistry in lecture formatswhere there is a one-way transmission of facts, where skills are learned by rote, and calculations are done by analogy to a worked example or by filling numbers into a formulaare unlikely to understand the increased depth required to teach to the NGSS. That is, if we



AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. Notes

Views expressed in this editorial are those of the author and not necessarily the views of the ACS.

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ACKNOWLEDGMENTS While the members of the NGSS writing team7 are too numerous to mention individually here, I thank them all. REFERENCES

(1) Achieve. Next Generation Science Standards;: National Research Council: Washington, DC, 2013. http://www.nextgenscience.org/ (accessed May 2013). (2) AAAS Project 2061. Benchmarks for Science Literacy; American Association for the Advancement of Science: Washington, DC, 1993. http://www.project2061.org/publications/bsl/ (accessed May 2013). (3) National Research Council. National Science Education Standards: Observe, Interact, Change, Learn; National Academy Press: Washington, DC, 1996. http://www.nap.edu/catalog.php?record_id=4962 (accessed May 2013). (4) Duschl, R. A.; Schweingruber, H. A.; Shouse, A. W. Taking Science to School; National Academies Press: Washington, DC, 2007. http:// www.nap.edu/catalog.php?record_id=11625 (accessed May 2013). (5) National Research Council. A Framework for K−12 Science Education: Practices, Crosscutting Concepts, and Core Ideas; The National Academies Press: Washington, DC, 2012. http://www.nap. edu/openbook.php?record_id=13165 (accessed May 2013). (6) Smith, C. L.; Wiser, M.; Anderson, C. W.; Krajcik, J. Implications of Research on Children’s Learning for Standards and Assessment: A Proposed Learning Progression for Matter and the Atomic-Molecular Theory. Meas: Interdiscip. Res. Perspect. 2006, 4, 1−98. http://dx.doi. org/10.1080/15366367.2006.9678570 (accessed May 2013). (7) Details about the writing team for the Next Generation Science Standards can be found online at http://www.nextgenscience.org/ writing-team (accessed May 2013).

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dx.doi.org/10.1021/ed400284c | J. Chem. Educ. 2013, 90, 679−680