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YSS May 2012 Science Education Standards

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By the end of the 2nd grade, students should know that

  • Water can be a liquid or a solid and can go back and forth from one form to the other. If water is turned into ice and then the ice is allowed to melt, the amount of water is the same as it was before freezing. 4B/P2

By the end of the 5th grade, students should know that

  • Science is a process of trying to figure out how the world works by making careful observations and trying to make sense of those observations. 1A/E2**
  • Scientists' explanations about what happens in the world come partly from what they observe, partly from what they think. 1B/E3a
  • Sometimes scientists have different explanations for the same set of observations. That usually leads to their making more observations to resolve the differences. 1B/E3bc

By the end of 8th grade, students should know that

  • Scientific knowledge is subject to modification as new information challenges prevailing theories and as a new theory leads to looking at old observations in a new way. 1A/M2
  • Scientific investigations usually involve the collection of relevant data, the use of logical reasoning, and the application of imagination in devising hypotheses and explanations to make sense of the collected data. 1B/M1b*

By the end of 12th grade, students should know that

  • From time to time, major shifts occur in the scientific view of how things work. More often, however, the changes that take place in the body of scientific knowledge are small modifications of prior knowledge. Continuity and change are persistent features of science. 1A/H2*
  • No matter how well one theory fits observations, a new theory might fit them just as well or better, or might fit a wider range of observations. 1A/H3a
  • In science, the testing, revising and occasional discarding of theories, new and old, never ends. This ongoing process leads to a better understanding of how things work in the world, but not to absolute truth. 1A/H3bc*
  • In the short run, new ideas that do not mesh well with mainstream ideas in science often encounter vigorous criticism. 1B/H6a
  • In the long run, theories are judged by the range of observations they explain, how well they explain observations and how useful they are in making accurate predictions. 1B/H6b*
  • New ideas in science are limited by the context in which they are conceived; are often rejected by the scientific establishment; sometimes spring from unexpected findings; and usually grow slowly, through contributions from many investigators. 1B/H7

National Science Education Standards

Grades K-4
Abilities Necessary to Do Scientific Inquiry
Understandings about Scientific Inquiry

  • Scientists develop explanations using observations (evidence) and what they already know about the world (scientific knowledge). Good explanations are based on evidence from investigations.
  • Scientists review and ask questions about the results of other scientists' work.

Grades 5-8
Abilities Necessary to Do Scientific Inquiry
Understandings about Scientific Inquiry

  • Scientific explanations emphasize evidence, have logically consistent arguments and use scientific principles, models and theories. The scientific community accepts and uses such explanations until displaced by better scientific ones. When such displacement occurs, science advances.
  • Science advances through legitimate skepticism. Asking questions and querying other scientists' explanations is part of scientific inquiry. Scientists evaluate the explanations proposed by other scientists by examining evidence, comparing evidence, identifying faulty reasoning, pointing out statements that go beyond the evidence, and suggesting alternative explanations for the same observations.

Nature of Science

  • Scientists formulate and test their explanations of nature using observation, experiments, and theoretical and mathematical models. Although all scientific ideas are tentative and subject to change and improvement in principle, for most major ideas in science, there is much experimental and observational confirmation. Those ideas are not likely to change greatly in the future. Scientists do and have changed their ideas about nature when they encounter new experimental evidence that does not match their existing explanations.
  • In areas where active research is being pursued and in which there is not a great deal of experimental or observational evidence and understanding, it is normal for scientists to differ with one another about the interpretation of the evidence or theory being considered. Different scientists might publish conflicting experimental results or might draw different conclusions from the same data. Ideally, scientists acknowledge such conflict and work towards finding evidence that will resolve their disagreement.

Grades 9-12
Abilities Necessary to Do Scientific Inquiry

  • Formulate And Revise Scientific Explanations And Models Using Logic And Evidence. Student inquiries should culminate in formulating an explanation or model. Models should be physical, conceptual and mathematical. In the process of answering the questions, the students should engage in discussions and arguments that result in the revision of their explanations. These discussions should be based on scientific knowledge, the use of logic and evidence from their investigation.
  • Recognize And Analyze Alternative Explanations And Models. This aspect of the standard emphasizes the critical abilities of analyzing an argument by reviewing current scientific understanding, weighing the evidence and examining the logic so as to decide which explanations and models are best. In other words, although there may be several plausible explanations, they do not all have equal weight. Students should be able to use scientific criteria to find the preferred explanations.

Nature of Scientific Knowledge

  • Scientific explanations must meet certain criteria. First and foremost, they must be consistent with experimental and observational evidence about nature, and must make accurate predictions, when appropriate, about systems being studied. They should also be logical, respect the rules of evidence, be open to criticism, report methods and procedures, and make knowledge public. Explanations on how the natural world changes based on myths, personal beliefs, religious values, mystical inspiration, superstition, or authority may be personally useful and socially relevant, but they are not scientific.
  • Because all scientific ideas depend on experimental and observational confirmation, all scientific knowledge is, in principle, subject to change as new evidence becomes available. The core ideas of science such as the conservation of energy or the laws of motion have been subjected to a wide variety of confirmations and are therefore unlikely to change in the areas in which they have been tested. In areas where data or understanding are incomplete, such as the details of human evolution or questions surrounding global warming, new data may well lead to changes in current ideas or resolve current conflicts. In situations where information is still fragmentary, it is normal for scientific ideas to be incomplete, but this is also where the opportunity for making advances may be greatest.

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Last Updated: 22 May 2012