The Next Generation Science Standards: 5. Crosscutting Concepts Professor Michael Wysession Department of Earth and Planetary Sciences Washington University, St. Louis, MO

Crosscutting Concepts 1. Patterns. Observed patterns of forms and events guide organization and classification, and they prompt questions about relationships and the factors that influence them. 2. Cause and effect: Mechanism and explanation. Events have causes, sometimes simple, sometimes multifaceted. A major activity of science is investigating and explaining causal relationships and the mechanisms by which they are mediated. Such mechanisms can then be tested across given contexts and used to predict and explain events in new contexts.

Crosscutting Concepts 3. Scale, proportion, and quantity. In considering phenomena, it is critical to recognize what is relevant at different measures of size, time, and energy and to recognize how changes in scale, proportion, or quantity affect a system’s structure or performance. 4. Systems and system models. Defining the system under study—specifying its boundaries and making explicit a model of that system—provides tools for understanding and testing ideas that are applicable throughout science and engineering.

Crosscutting Concepts 5. Energy and matter: Flows, cycles, and conservation. Tracking fluxes of energy and matter into, out of, and within systems helps one understand the systems’ possibilities and limitations. 6. Structure and function. The way in which an object or living thing is shaped and its substructure determine many of its properties and functions. 7. Stability and change. For natural and built systems alike, conditions of stability and determinants of rates of change or evolution of a system are critical elements of study.

Connections among the Crosscutting Concepts Structure and Dimension: There are strong connections between the crosscutting concepts of “Patterns” and “Scale, Proportion, and Quantity.” Both are ways of observing, categorizing, and classifying information, whether about physical objects or phenomena. While they are both necessary for the eventual interpretation of information in terms of function or process, they themselves are more static, capable of conveying meaning without the inference of function. Even when examining time scales, such as the geologic time scale, this is done in a more passive way, isolated from the associated processes that are involved.

Connections among the Crosscutting Concepts Causality of Components: “Structure and Function” and “Cause and Effect” take a reductionist view, focusing on processes of individual system components. One approach of science is to break a system into its fundamental structures, identifying the function of each, as well as an associated set of independent causes and effects. “Structure and Function” involves the identification of the physical structures of nature, but takes them a step further by identifying the functions of these components. “Cause and Effect” brings a temporal aspect to function by examining a sequence of events. If one action occurs, then the functional nature of objects causes a predictable set or sequence of outcomes.

Connections among the Crosscutting Concepts Systems: A contrasting approach to science is to examine a system as a whole. You can take apart a radio and understand the separate structure and function of each of its components, but you won’t hear any music until you put them together and study them as a system. This holistic approach of science, the opposite of the reductionist approach, is exemplified by the other crosscutting concepts of “Systems and System Models,” “Energy and Matter,” and “Stability and Change.” These all deal with understanding nature by examining how components of a system function together, where “cause and effect” processes are now complicated by the multiple interactions among them. “Systems and System Models” is the broadest concept of the three, establishing the scientific approach of understanding an interconnected system in its totality.

Crosscutting Concepts Middle School Distribution of Crosscutting Concepts:

Crosscutting Concepts: 1. Patterns

Crosscutting Concepts: 2. Cause and Effect

Crosscutting Concepts: 3. Scale, Proportion, and Quantity

Crosscutting Concepts: 4. Systems and System Models

Crosscutting Concepts: 5. Energy and Matter

Crosscutting Concepts: 6. Structure and Function

Crosscutting Concepts: 7. Stability and Change