NGSS Nature of Science Thread:
Science Is a Way of Knowing

Science knowledge has a history that includes the refinement of, and changes to, theories, ideas, and beliefs over time.

Related Science and Engineering Practices

Practice 2: Developing and Using Models

  • Evaluate merits and limitations of two different models of the same proposed tool, process, mechanism or system in order to select or revise a model that best fits the evidence or design criteria.

  • Design a test of a model to ascertain its reliability.

  • Develop, revise, and/or use a model based on evidence to illustrate and/or predict the relationships between systems or between components of a system.

  • Develop and/or use multiple types of models to provide mechanistic accounts and/or predict phenomena, and move flexibly between model types based on merits and limitations.

  • Develop a complex model that allows for manipulation and testing of a proposed process or system.

  • Develop and/or use a model (including mathematical and computational) to generate data to support explanations, predict phenomena, analyze systems, and/or solve problems.

Practice 7: Engaging in Argument from Evidence

  • Compare and evaluate competing arguments or design solutions in light of currently accepted explanations, new evidence, limitations (e.g., trade-offs), constraints, and ethical issues.

  • Evaluate the claims, evidence, and/or reasoning behind currently accepted explanations or solutions to determine the merits of arguments.

  • Respectfully provide and/or receive critiques on scientific arguments by probing reasoning and evidence, challenging ideas and conclusions, responding thoughtfully to diverse perspectives, and determining additional information required to resolve contradictions.

  • Construct, use, and/or present an oral and written argument or counter-arguments based on data and evidence.

  • Make and defend a claim based on evidence about the natural world or the effectiveness of a design solution that reflects scientific knowledge and student generated evidence.

  • Evaluate competing design solutions to a real-world problem based on scientific ideas and principles, empirical evidence, and/or logical arguments regarding relevant factors (e.g. economic, societal, environmental, ethical considerations).

Related Crosscutting Concepts

1. Patterns

Observed patterns of forms and events guide organization and classification and prompt questions about relationships and the factors that influence them.

Performance Expectations and Disciplinary Core Ideas by Subject

Biology

Performance Standards

  • HS-LS2 – ECOSYSTEMS: INTERACTIONS, ENERGY, AND DYNAMICS

    • HS-LS2-3: Construct and revise an explanation based on evidence for the cycling of matter and flow of energy in aerobic and anaerobic conditions.

Disciplinary Core Ideas

  • LS1: FROM MOLECULES TO ORGANISMS: STRUCTURES AND PROCESSES

    • LS1.B: Growth and Development of Organisms

      • In multicellular organisms individual cells grow and then divide via a process called mitosis, thereby allowing the organism to grow. The organism begins as a single cell (fertilized egg) that divides successively to produce many cells, with each parent cell passing identical genetic material (two variants of each chromosome pair) to both daughter cells. Cellular division and differentiation produce and maintain a complex organism, composed of systems of tissues and organs that work together to meet the needs of the whole organism.

  • LS3: HEREDITY: INHERITANCE AND VARIATION OF TRAITS

    • LS3.A: Inheritance of Traits

      • Each chromosome consists of a single very long DNA molecule, and each gene on the chromosome is a particular segment of that DNA. The instructions for forming species’ characteristics are carried in DNA. All cells in an organism have the same genetic content, but the genes used (expressed) by the cell may be regulated in different ways. Not all DNA codes for a protein; some segments of DNA are involved in regulatory or structural functions, and some have no as-yet known function.

  • LS4: BIOLOGICAL EVOLUTION: UNITY AND DIVERSITY

    • LS4.B: Natural Selection

      • Natural selection occurs only if there is both (1) variation in the genetic information between organisms in a population and (2) variation in the expression of that genetic information—that is, trait variation—that leads to differences in performance among individuals.

      • The traits that positively affect survival are more likely to be reproduced, and thus are more common in the population.

    • LS4.C: Adaptation

      • Evolution is a consequence of the interaction of four factors: (1) the potential for a species to increase in number, (2) the genetic variation of individuals in a species due to mutation and sexual reproduction, (3) competition for an environment’s limited supply of the resources that individuals need in order to survive and reproduce, and (4) the ensuing proliferation of those organisms that are better able to survive and reproduce in that environment.

      • Natural selection leads to adaptation, that is, to a population dominated by organisms that are anatomically, behaviorally, and physiologically well suited to survive and reproduce in a specific environment. That is, the differential survival and reproduction of organisms in a population that have an advantageous heritable trait leads to an increase in the proportion of individuals in future generations that have the trait and to a decrease in the proportion of individuals that do not.

      • Adaptation also means that the distribution of traits in a population can change when conditions change.

      • Changes in the physical environment, whether naturally occurring or human induced, have thus contributed to the expansion of some species, the emergence of new distinct species as populations diverge under different conditions, and the decline–and sometimes the extinction–of some species.

      • Species become extinct because they can no longer survive and reproduce in their altered environment. If members cannot adjust to change that is too fast or drastic, the opportunity for the species’ evolution is lost.

Chemistry

Performance Standards

  • HS-PS4 – WAVES AND THEIR APPLICATIONS IN TECHNOLOGIES FOR INFORMATION TRANSFER

    • HS-PS4-3: Evaluate the claims, evidence, and reasoning behind the idea that electromagnetic radiation can be described either by a wave model or a particle model, and that for some situations one model is more useful than the other.

Disciplinary Core Ideas

  • PS4: WAVES AND THEIR APPLICATIONS IN TECHNOLOGIES FOR INFORMATION TRANSFER

    • PS4.B: Electromagnetic Radiation

      • Electromagnetic radiation (e.g., radio, microwaves, light) can be modeled as a wave of changing electric and magnetic fields or as particles called photons. The wave model is useful for explaining many features of electromagnetic radiation, and the particle model explains other features.

      • When light or longer wavelength electromagnetic radiation is absorbed in matter, it is generally converted into thermal energy (heat). Shorter wavelength electromagnetic radiation (ultraviolet, X-rays, gamma rays) can ionize atoms and cause damage to living cells.

      • Photoelectric materials emit electrons when they absorb light of a high-enough frequency.

      • Atoms of each element emit and absorb characteristic frequencies of light. These characteristics allow identification of the presence of an element, even in microscopic quantities.

Physics

Performance Standards

  • HS-PS2 – MOTION AND STABILITY: FORCES AND INTERACTIONS

    • HS-PS2-1: Analyze data to support the claim that Newton’s second law of motion describes the mathematical relationship among the net force on a macroscopic object, its mass, and its acceleration.

Disciplinary Core Ideas

  • PS2: MOTION AND STABILITY: FORCES AND INTERACTIONS

    • PS2.B: Types of Interactions

      • Newton’s law of universal gravitation and Coulomb’s law provide the mathematical models to describe and predict the effects of gravitational and electrostatic forces between distant objects.

      • Forces at a distance are explained by fields (gravitational, electric, and magnetic) permeating space that can transfer energy through space. Magnets or electric currents cause magnetic fields; electric charges or changing magnetic fields cause electric fields.

      • Attraction and repulsion between electric charges at the atomic scale explain the structure, properties, and transformations of matter, as ell as the contact forces between material objects. (HS-PS1-1), (secondary to HS-PS1-3)

  • PS3: ENERGY

    • PS3.A: Definitions of Energy

      • Energy is a quantitative property of a system that depends on the motion and interactions of matter and radiation within that system. That there is a single quantity called energy is due to the fact that a system’s total energy is conserved, even as, within the system, energy is continually transferred from one object to another and between its various possible forms.

      • At the macroscopic scale, energy manifests itself in multiple ways, such as in motion, sound, light, and thermal energy.

      • These relationships are better understood at the microscopic scale, at which all of the different manifestations of energy can be modeled as a combination of energy associated with the motion of particles and energy associated with the configuration (relative position of the particles). In some cases the relative position energy can be thought of as stored in fields (which mediate interactions between particles). This last concept includes radiation, a phenomenon in which energy stored in fields moves across space.