Science and Engineering Practices

Next Generation Science Standards

Scientific and Engineering Practices

1. Asking questions (for science) and defining problems (for engineering)

2. Developing and using models3. Planning and carrying out investigations4. Analyzing and interpreting data5. Using mathematics and computational thinking6. Constructing explanations (for science) and designing

solutions (for engineering)7. Engaging in argument from evidence8. Obtaining, evaluating, and communicating information

Practice 1: Asking Questions and Defining Problems

Questions are the engine that drive science and engineering. Science asks:• What exists and what happens?• Why does it happen?• How does one know?Engineering asks:• What can be done to address a particular human need or want?• How can the need be better specified?• What tools and technologies are available, or could be developed, for

addressing this need?Both science and engineering ask:• How does one communicate phenomena, evidence, explanations, and

design solutions?

Practice 2: Developing and Using Models

• Mental models are internal, personal, unstable, and essentially functional.

• Conceptual models are in some ways analogous to the phenomena they represent.

• Models bring certain features into focus while minimizing or obscuring others. All models contain approximations and assumptions that limit the range of validity.

Science use of models

Scientists use models • to represent their current understanding of a

system• to aid in the development of questions and

explanations• to communicate ideas to others

Engineering Use of Models

Engineering makes use of models • to analyze existing systems– to see under what conditions flaws might develop – to test possible solutions to a new problem.

• to visualize a design and take it to a higher level of refinement

• to communicate a design’s features to others• as prototypes for testing design performance

Practice 3: Planning and Carrying Out Investigations

Scientists and engineers investigate and observe the world with essentially two goals: (1) to systematically describe the world (2) to develop and test theories and

explanations of how the world works.

Practice 4: Analyzing and Interpreting Data

Data must be presented in a form that can reveal any patterns and relationships and that allows results to be communicated to others. • Scientists organize and interpret the data through

tabulating, graphing, or statistical analysis. • Engineers often analyze a design by creating a

model or prototype and collecting extensive data on how it performs, including under extreme conditions.

Practice 4: Analyzing and Interpreting Data

Spreadsheets and databases provide useful ways of organizing data, especially large data sets. • Tables summarize major features of a large

body of data• Graphs visually summarize data• Mathematics expresses relationships between

different variables in the data set

Practice 5: Using Mathematics, Information and Computer Technology, and

Computational Thinking• Mathematics enables ideas to be expressed in

a precise form and enables the identification of new ideas about the physical world.

• Predictions and inferences can have a probabilistic nature (like genetics).

Engineering uses mathematical and computational skills. • Structural engineers create mathematical models of bridge and

building designs, based on physical laws– to test their performance– probe their structural limits– assess whether they can be completed within acceptable budgets.

Mathematics often brings science and engineering together • by enabling engineers to apply the mathematical form of scientific

theories • by enabling scientists to use powerful information technologies

designed by engineers.

Practice 5: Using Mathematics, Information and Computer Technology, and

Computational Thinking

Practice 6: Constructing Explanations and Designing Solutions

• Scientific theories are developed – to provide explanations– predict future events– make inferences about past events

• Scientific theories – are constructs based on significant bodies of knowledge and evidence– are revised in light of new evidence– must withstand significant scrutiny

• Scientific Hypothesis– neither a scientific theory nor a guess– a specific expectation about what will happen in a given situation– made based on existing theories

Practice 6: Constructing Explanations and Designing Solutions

Engineers’ activities have elements that are distinct from those of scientists:• specifying constraints and criteria• developing a design plan• producing and testing models or prototypes• selecting among alternative design features to

optimize the achievement of design criteria• refining design ideas based on the performance

of a prototype or simulation

Practice 7: Engaging in Argument from Evidence

• In science, the production of knowledge is dependent on a process of reasoning that requires a scientist to make a justified claim about the world.

• In response, other scientists attempt to identify the claim’s weaknesses and limitations.

• Argumentation is also needed to resolve questions involving, for example, the best experimental design, the most appropriate techniques of data analysis, or the best interpretation of a given data set.

Practice 7: Engaging in Argument from Evidence

• In engineering, reasoning and argument are essential to finding the best possible solution to a problem.

• At an early design stage, competing ideas must be compared (and possibly combined) to achieve an initial design

• At a later stage in the design process, engineers test their potential solution, collect data, and modify their design in an iterative manner

• The results of such efforts are often presented as evidence to argue about the strengths and weaknesses of a particular design

Practice 7: Engaging in Argument from Evidence

• The criteria employed in engineering are often quite different from those of science.

• For example, engineers might use – cost-benefit analysis– an analysis of risk– an appeal to aesthetics– predictions about market reception

to justify why one design is better than another—or why an entirely different course of action should be followed.

Practice 8: Obtaining, Evaluating, and Communicating Information

Reading in science is often challenging to students• Use of jargon, passive voice, and complex sentence structure• The precise meaning of each word or clause may be

important (different than reading a novel) • Science texts are multimodal (use a mix of words, diagrams,

charts, symbols, and mathematics)

Communicating in written or spoken form is a fundamental practice of science; requiring scientists to • describe observations precisely• clarify their thinking• justify their arguments.

Practice 8: Obtaining, Evaluating, and Communicating Information

Being a critical consumer of science and the products of engineering, whether as a lay citizen or a practicing scientist or engineer, also requires the ability • to read or view reports about science in the press or on

the Internet • to recognize the salient science• identify sources of error and methodological flaws• distinguish observations from inferences, arguments

from explanations, and claims from evidence.