NRC Science Education Standards

Project 2061 Benchmarks

(www.npa.edu)

Content Standard: Unifying Concepts & Processes (pp. 115-119)

Fundamental concepts that underlie Systems, Order, & Organization include:

• A system is an organized group of related objects or components that form a whole. Systems can coexist, for example, of organisms, machines, fundamental particles, galaxies, ideas, numbers, transportation, and education.
• Systems have boundaries, components, resources flow (input and output), and feedback.
• Think and analyze in terms of systems.
• The idea of simple systems encompasses subsystems as well as identifying the structure and function of systems, feedback and equilibrium, and the distinction between open and closed systems.

Fundamental concepts that underlie Evidence, Models, & Explanation include:

• Evidence consists of observations and data on which to base scientific explanations.

Fundamental concepts that underlie Constancy, Change, and Measurement include:

• Interactions within and among systems result in change.
• Changes vary in rate, scale, and pattern, including trends and cycles.
• Energy can be transferred and matter can be changed.
• Changes in systems can be quantified.
• Evidence for interactions and subsequent change and the formulation of scientific explanations are often clarified through quantitative distinctions-measurement.
• Mathematics is essential for accurately measuring change.
• Different systems of measurement are used for different purposes.
• An important part of measurement is knowing when to use which system.
• Scale includes understanding that different characteristics, properties, or relationships within a system might change as its dimensions are increased or decreased.
• Rate involves comparing one measured quantity with

Content Standard A: Science as Inquiry (pp. 173-176)

Fundamental abilities and concepts that underlie the Abilities Necessary to Do Scientific Inquiry include:

• Identify questions and concepts that guide scientific investigations.
• Formulate and revise scientific explanations and models using logic and evidence.
• Recognize and analyze alternative explanations and models.
• Communicate and defend a scientific argument.

Fundamental concepts that underlie the Understandings About Scientific Inquiry include:

• Historical and current scientific knowledge influence the design and interpretation of investigations and the evaluation of proposed explanations made by other scientists.
• Scientists conduct investigations for a wide variety of reasons:
  • to discover new aspects of the natural world,
  • to explain recently observed phenomena,
  • to test the conclusions of prior investigations or the predictions of current theories.
  • Scientists rely on technology to enhance the gathering and manipulation of data.
  • New techniques and tools provide new evidence to guide inquiry and new methods to gather data, thereby contributing to the advance of science.
  • The accuracy and precision of the data, and therefore the quality of the exploration, depends on the technology used.
  • Mathematics is essential in scientific inquiry. Mathematical tools and models guide and improve the posing of questions, gathering data, constructing explanations and communicating results.
• Scientific explanations must adhere to criteria such as:
  • a proposed explanation must be logically consistent;
  • it must abide by the rules of evidence; it must be open to questions and possible modification;
  • and it must be based on historical and current scientific knowledge.
  • Results of scientific inquiry-new knowledge and methods-emerge from different types of investigations and public communication among scientists.
  • In communicating and defending the results of scientific inquiry, arguments must be logical and demonstrate connections between natural phenomena, investigations, and the historical body of scientific knowledge.
  • The methods and procedures that scientists used to obtain evidence must be clearly reported to enhance opportunities for further investigation.

Content Standard B: Physical Science (pp. 176-181)

Fundamental concepts that underlie Structure of Atoms include:

• Matter is made of minute particles called atoms, and atoms are composed of even smaller components.
• Each atom has a positively charged nucleus surrounded by negatively charged electrons.
• The electric force between the nucleus and electrons holds the atom together.
• The atom's nucleus is composed of protons and neutrons.

Fundamental concepts that underlie Structure & Properties of Matter include:

• Atoms interact with one another by transferring or sharing electrons that are furthest from the nucleus.
• Outer electrons govern the chemical properties of the element.
• Bonds between atoms are created when electrons are paired up by being transferred or shared.
• A substance composed of a single kind of atom is called an element.
• A compound is formed when two or more kinds of atoms bind together chemically.

Fundamental concepts that underlie Chemical Reactions include:

• A large number of important reactions involve the transfer of either electrons (oxidation/reduction reactions) or hydrogen ions (acid/base reactions) between reacting ions, molecules, or atoms.
• Chemical bonds are broken by heat or light to form very reactive radicals with electrons ready to form new bonds.
• Radical reactions control many processes such as the presence of ozone and greenhouse gases in the atmosphere, burning and processing of fossil fuels, the formation of polymers, and explosions.
• Chemical reactions can take place in time periods ranging from the few (1- -15 seconds) required for an atom to move a fraction of a chemical bond distance to geologic time scales of billions of years.
• Reaction rates depend on how often the reacting atoms and molecules encounter one another, on the temperature, and on the properties- including shape-of the reacting species.

Fundamental concepts that underlie Interactions of Energy & Matter include:

• Waves, including sound and seismic waves, waves on water, and light waves, have energy and can transfer energy when they interact with matter.
• The energy of electromagnetic waves is carried in packets whose magnitude is inversely proportional to the wavelength.

Content Standard C: Life Science (pp. 181-187)

Fundamental concepts that underlie the Molecular Basis of Heredity include:

• In all organisms, the instructions for specifying the characteristics of the organism are carried in DNA, a large polymer formed from subunits of four kinds (A, G, C, and T).
• The chemical and structural properties of DNA explain how the genetic information that underlies heredity is both encoded in genes (as a string of molecular "letters") and replicated (by a templating mechanism). Each DNA molecule in a cell forms a single chromosome.
• Changes in DNA (mutations) occur spontaneously at low rates. Some of these changes make no difference to the organ ism, whereas others can change cells and organisms. Only mutations in germ cells can create the variation that changes an organism's offspring.

Fundamental concepts that underlie the Interdependence of Organisms include:

• Human beings live within the world's ecosystems. Increasingly, humans modify ecosystems as a result of population growth, technology, and consumption.
• Human destruction of habitats through direct harvesting, pollution, atmospheric changes, and other factors is threatening current global stability, and if not addressed, ecosystems will be irreversibly affected.

Content Standard F: Science in Personal & Social Perspectives (pp. 193-199)

Fundamental concepts that underlie the Population Growth include:

• Populations can increase through linear or exponential growth, with effects on resource use and environmental pollution.
• Changes in technology can cause significant changes, either positive or negative, in carrying capacity.

Fundamental concepts that underlie the Environmental Quality include:

• Materials from human societies affect both physical and chemical cycles of the earth.
• Factors that students might investigate include population growth, resource use, population distribution, overconsumption, the capacity of technology to solve problems, poverty, the role of economic, political, and religious views, and different ways humans view the earth.

Fundamental concepts that underlie the Natural & Human-Induced Hazards include:

• Normal adjustments of earth may be hazardous forumans.
• Humans live at the interface between the atmosphere driven by solar energy and the upper mantle where convection creates changes in the earth's solid crust.
• As societies have grown, become stable, and come to value aspects of the environment, vulnerability to natural processes of change has increased. Human activities can enhance potential for hazards.
• Acquisition of resources, urban growth, and waste disposal can accelerate rates of natural change.
• Some hazards, such as earthquakes, volcanic eruptions, and severe weather, are rapid and spectacular.
• Natural and human-induced hazards present the need for humans to assess potential danger and risk.
• Many changes in the environment designed by humans bring benefits to society, as well as cause risks.
• Students should understand the costs and trade-offs of various hazards-ranging from those with minor risk to a few people to major catastrophes with major risk to many people.
• The scale of events and the accuracy with which scientists and engineers can (and cannot) predict events are important considerations.

Fundamental concepts that underlie Science & Technology in Local, Natioanl, & Global Challenges include:

• Science and technology are essential social enterprises, but alone they can only indicate what can happen, not what should happen. The latter involves human decisions about the use of knowledge.
• Decisions involve assessment of alternatives, risks, costs, and benefits and consideration of who benefits and who suffers, who pays and gains, and what the risks are and who bears them.
• Students should understand the appropriateness and value of basic questions-"What can happen?"- "What are the odds?"-and "How do scientists and engineers know what will happen?"
• Humans have a major effect on other species. For example, the influence of humans on other organisms occurs through land use-which decreases space available to other species-and pollution-which changes the chemical composition of air, soil, and water.

Content Standard E: Science & Technology (pp. 190-193)

Fundamental concepts that underlie Abilities of Technological Design include:

• Identify a problem or design an opportunity.
• Propose designs and choose between alternative solutions.
• Implement a proposed solution.
• Evaluate the solution and its consequences.
• Communicate the problem, process, and solution.

Fundamental concepts that underlie Understandings About Science & Technology include:

• Scientists in different disciplines ask different questions, use different methods of investigation, and accept different types of evidence to support their explanations.
• Many scientific investigations require the contributions of individuals from diffeent disciplines, including engineering.
• New disciplines of science, such as geophysics and biochemistry often emerge at the interface of two older discplines.

Content Standard G: History & Nature of Science (pp. 200-201)

Fundamental concepts that underlie Nature of Scientific Knowledge include:

• Science distinguishes itself from other ways of knowing and from other bodies of knowledge through the use of empiricalstandards, logical arguments, and skepticism, as scientists strive for the best possible explanations about the natural world.
• 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.
• Scientific explanations should also be logical, respect the rules of evidence, be open to criticism, report methods and procedures, and make knowledge public.
• Because all scientific ideas depend on experimental and observational confirmation, all scientific knowledge is, in principle, subject to change as new evidence becomes available.
• In areas where data or understanding are incomplete, such as the details of human evolution or questions surrounding global warming, new data may well ead 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.

Content Standard: Chapter 11, Common Themes

11A Systems:

• A system usually has some properties that are different from those of its parts, but appear because of the interaction of those parts.
• Understanding how things work and designing solutions to problems of almost any kind can be facilitated by systems analysis.
• In defining a system, it is important to specify its boundaries and subsystems, indicate its relation to other systems, and identify what its input and its output are expected to be.
• The successful operation of a designed system usually involves feedback. The stability of a system can be greater when it includes appropriate feedback mechanisms.
• Even in some very simple systems, it may not always be possible to predict accurately the result of changing some part or connection.

11B Models:

• The basic idea of mathematical modeling is to find a mathematical relationship that behaves in the same ways as the objects or processes under investigation.
• Computers have greatly improved the power and use of mathematical models by performing computations that are very long, very complicated, or repetitive.
• The graphic capabilities of computers make them useful in the design and testing of devices and structures and in the simulation of complicated processes.
• The usefulness of a model can be tested by comparing its predictions to actual observations in the real world.

11C Constancy and Change:

• A system in equilibrium may return to the same state of equilibrium if the disturbances it experiences are small.
• Large disturbances may cause it to escape that equilibrium and eventually settle into some other state of equilibrium.
• Graphs and equations are useful (and often equivalent) ways for depicting and analyzing patterns of change.
• Most systems above the molecular level involve so many parts and forces and are so sensitive to tiny differences in conditions that their precise behavior is unpredictable, even if all the rules for change are known.
• Predictable or not, the precise future of a system is not completely determined by its present state and circumstances but also depends on the fundamentally uncertain outcomes of events on the atomic scale.

Content Standard: Chapter 1, The Nature of Science

1A The Scientific World View:

• Scientists assume that the universe is a vast single system in which the basic rules are the same everywhere.
• Change and continuity are persistent features of science.
• In science, the testing, revising, and occasional discarding of theories, new and old never ends.
• Science is an ongoing process leads to an increasingly better understanding of how things work in the world but not to absolute truth.

1B Scientific Inquiry:

• Investigations are conducted for different reasons, including to explore new phenomena, to check on previous results, to test how well a theory predicts, and to compare different theories.
• Hypotheses are widely used in science for choosing what data to pay attention to and what additional data to seek, and for guiding the interpretation of the data (both new and previously available).
• Sometimes, scientists can control conditions in order to obtain evidence. When that is not possible for practical or ethical reasons, they try to observe as wide a range of natural occurrences as possible to be able to discern patterns.
• There are different traditions in science about what is investigated and how, but they all have in common certain basic beliefs about the value of evidence, logic, and good arguments. And there is agreement that progress in all fields of science depends on intelligence, hard work, imagination, and even chance.
• Scientists in any one research group tend to see things alike, so even groups of scientists may have trouble being entirely objective about their methods and findings. For that reason, scientific teams are expected to seek out the possible sources of bias in the design of their investigations and in their data analysis. Checking each other's results and explanations helps, but that is no guarantee against bias.
• In the short run, new ideas that do not mesh well with mainstream ideas in science often encounter vigorous criticism. In the long run, theories are judged by how they fit with other theories, the range of observations they explain, how well they explain observations, and how effective they are in predicting new findings.
• 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.

1C The Scientific Enterprise:

• Progress in science and invention depends heavily on what else is happening in society, and history often depends on scientific and technological developments.
• Science disciplines differ from one another in what is studied, techniques used, and outcomes sought, but they share a common purpose and philosophy, and all are part of the same scientific enterprise.
• Many problems are studied by scientists using information and skills from many disciplines.
• Disciplines do not have fixed boundaries, and it happens that new scientific disciplines are being formed where existing ones meet and that some subdisciplines spin off to become new disciplines in their own right.
• Scientists can bring information, insights, and analytical skills to bear on matters of public concern.
• Scientists as a group can be expected to be no less biased than other groups are about their perceived interests.
• The strongly held traditions of science, including its commitment to peer review and publication, serve to keep the vast majority of scientists well within the bounds of ethical professional behavior. Deliberate deceit is rare and likely to be exposed sooner or later by the scientific enterprise itself.
• Funding influences the direction of science by virtue of the decisions that are made on which research to support.

Content Standard: Chapter 4, The Physical Setting

4D Structure of Matter:

• Atoms:
  • are made of a positive nucleus surrounded by negative electrons.
  • electron configuration, particularly the outermost electrons, determines how the atom can interact with other atoms.
  • form bonds to other atoms by transferring or sharing electrons.
• In a neutral atom, the number of electrons equals the number of protons.
• Atoms may acquire an unbalanced charge by gaining or losing electrons.

4E Energy Transformations:

• Different energy levels are associated with different configurations of atoms and molecules. Some changes of configuration require an input of energy whereas others release energy.
• When energy of an isolated atom or molecule changes, it does so in a definite jump from one value to another, with no possible values in between. The change in energy occurs when radiation is absorbed or emitted, so the radiation also has distinct energy values.
• Light energy emitted or absorbed by separate atoms or molecules (as in a gas) can be used to identify what the substance is.

4B The Earth:

• Life is adapted to conditions on the earth, including the force of gravity that enables the planet to retain an adequate atmosphere, and an intensity of radiation from the sun that allows water to cycle between liquid and vapor.

Content Standard: Chapter 5, The Living Environment

5C Cells:

• The function of each protein molecule depends on its specific sequence of amino acids and the shape the chain takes is a consequence of attractions between the chain's parts
• The genetic information in DNA molecules provides instructions for assembling protein molecules. The code used is virtually the same for all life forms.
• Gene mutation in a cell can result in uncontrolled cell division, called cancer. Exposure of cells to certain chemicals and radiation increases mutations and thus increases the chance of cancer.

5B Heredity:

• Gene mutations can be caused by such things as radiation and chemicals.

5D Interdependence of Life:

• Ecosystems can be reasonably stable over hundreds or thousandsof years. As any population of organisms grows, it is held in check by one or more environmental factors: depletion of food or nesting sites, increased loss to increased numbers of predators, or parasites. If a disaster such as flood or fire occurs, the damaged ecosystem is likely to recover in stages that eventually result in a system similar to the original one.
• Human beings are part of the earth's ecosystems.
• Human activities can, deliberately or inadvertently, alter the equilibrium in ecosystems.

Content Standard: Chapter 7, Human Society

7C Social Change:

• The size and rate of growth of the human population in any location is affected by economic, political, religious, technological, and environmental factors. Some of these factors, in turn, are influenced by the size and rate of growth of the population.
• The decisions of one generation both provide and limit the range of possibilities open to the next generation.
• Mass media, migrations, and conquest affect social change by exposing one culture to another.

7D Social Trade-offs:

• Benefits and costs of proposed choices include consequences that are long-term as well as short-term, and indirect as well as direct.
• The more remote the consequences of a personal or social decision, the harder it usually is to take them into account in considering alternatives.
• Benifits and costs may be difficult to estimate.
• In deciding among alternatives, a major question is who will receive the benefits and who (not necessarily the same people) will bear the costs.
• Social trade-offs are often generational:
  • The cost of benefits received by one generation may fall on subsequent generations.
  • The cost of a social trade-off is sometimes borne by one generation although the benefits are enjoyed by their descendants.

Content Standard: Chapter 12, Habits of Mind

12A Values and Attitudes:

• Know why curiosity, honesty, openness, and skepticism are so highly regarded in science and how they are incorporated into the way science is carried out; exhibit those traits in their own lives and value them in others.
• View science and technology thoughtfully, being neither categorically antagonistic nor uncritically positive.

12B Computation and Estimation:

• Use ratios and proportions, including constant rates, in appropriate problems.
• Find answers to problems by substituting numerical values in simple algebraic formulas and judge whether the answer is reasonable by reviewing the process and checking against typical values.
• Use computer spreadsheet, graphing, and database programs to assist in quantitative analysis.
• Compare data for two groups by representing their averages and spreads graphically.
• Express and compare very small and very large numbers using powers-of-ten notation.
• Consider the possible effects of measurement errors on calculations.

12D Communication Skills:

• Choose appropriate summary statistics to describe group differences, always indicating the spread of the data as well as the data's central tendencies.
• Describe spatial relationships in geometric terms such as perpendicular, parallel, tangent, similar, congruent, and symmetrical.
• Use and correctly interpret relational terms such as if . . . then . . . , and, or, sufficient, necessary, some, every, not, correlates with, and causes.
• Participate in group discussions on scientific topics by restating or summarizing accurately what others have said, asking for clarification or elaboration, and expressing alternative positions.
• Use tables, charts, and graphs in making arguments and claims in oral and written presentations.