WHY THE NEXT GENERATION SCIENCE STANDARDS?
Science Educators developed the Next Generation Science Standards(NGSS) primarily to help teachers teach science in a way that will
- engage students. In other words, teachers should use activities that will allow students interact and question their own thinking as they learn science concepts
- make students active participants in the learning process. In other words, teachers should provide hands-on activities so that students can explore and discover things on their own as they construct knowledge.
- provide context in which science concepts can be learned. In other words, teachers should not teach science as list of isolated facts, but rather, use hands-on activities to help students make sense of these concepts as they learn them.
THE THREE-DIMENSIONALITY OF NGSS
The Next Generation Science Standards (NGSS) integrates Disciplinary Core Ideas (DCI), Crosscutting Concepts, Science, and Engineering Practices. Together, these parts are usually referred as the three-dimensionality of NGSS. Visually, we can illustrate this three-dimensionality as:
WHAT ARE DISCIPLINARY CORE IDEAS (DCI)?
Disciplinary Core Ideas are the “big ideas” in every discipline or across disciplines. For instance, some core ideas in chemistry are energy and the atomic theory.
Disciplinary Core Ideas are grouped under four domains. These domains are:
- Life Sciences (LF)
- Earth and Space Sciences (ESS)
- Physical Sciences (PS)
- Engineering, Technology, and the Application of Science (ETS)
For Life Sciences, the core ideas are:
- Molecules to Organisms: Structures and Processes
- Ecosystems: Interactions, Energy, and Dynamics
- Heredity: Inheritance and Variation of Traits
- Biological Evolution: Unity and Diversity
For Earth and Space Sciences, the core ideas are:
- Earth’s Place in the Universe
- Earth’s Systems
- Earth and Human Activity
For Physical Sciences, the core ideas are:
- Matter and Its Interactions
- Motion and Stability: Forces and Interactions
- Energy
- Waves and Their Applications in Technologies for Information Transfer
For Engineering, Technology, and the Application of Science, the core idea is:
- Engineering design
WHAT ARE CROSSCUTTING CONCEPTS?
Crosscutting concepts are concepts that cut across all domains. They are:
Patterns
Scientists observe natural phenomena to find patterns. These patterns help scientists:
- classify
- organize
- question relationships and the causes behind them
Elementary and middle school students can be introduced to patterns when asked to sort objects according to color or size. They can also study and use the different properties of matter to determine whether a substance is a solid, liquid, or gas.
Cause and Effect
In our world, there are no effects without causes. Because of this, scientists can design careful experiments to uncover cause and effect relationships.
For example, elementary and middle school students can learn more about cause and effect relationships when asked to investigate the effect of light and water on plants or seeds growth.
Scale, Proportion, and Quantity
Matter and energy vary in quantity. Certain natural phenomena can only exist within certain sizes or quantities. As the scale changes, it’s necessary to recognize what properties are relevant. It’s also relevant to recognize the proportional relationships between these properties. For example, a solid object is formed from a collection of several molecules put together. Its physical properties of color, shape, and volume suddenly disappear when this same object is examined at the molecular level before the molecules were assembled to form it. To help students get a sense of scale and proportion, they can be asked to imagine a mouse and a horse. And then asked to figure out what features of a mouse would need to change for it to successfully live as a horse.
Systems and System Models
A system is a whole that consist of related parts put together according to a scheme. System models are things scientists create to represent a system and how its parts interact. System models are used to understand, explain, and predict system behavior.
For example, elementary and middle school students can learn about models when asked to observe in a microscope and draw pictures of a cell. They can also describe the cell’s parts and how these parts relate to one another. They can also draw models to describe the air they feel around them.
Energy and Matter
Energy is a property of matter. Without energy the universe dies. We can track energy as it flows into, within, and out of matter or system to understand its behavior. For example, students can study phase changes of water to understand how energy interacts with matter. Students can also study the water cycle to understand how energy flows into, within, and out of a system to understand its behavior. Students can also study chemical reactions to understand how energy is released when old bonds break and new bonds form.
Structure and Function
The form of something can determine its function. Fishes have fins and gills because the fins allow them to swim in water, while the gills allow them to breathe in water.
Stability and Change
Matter undergoes change. However, some changes may be too slow, while others may be too fast to observe with our eyes. As a result, it’s relevant to understand the causes of these changes and the factors that can affect the rate of change.
Stability is a state in which a system appears unchanging as a result of competing forces acting on the system. When these competing forces are balanced, an equilibrium is established. An equilibrium becomes dynamic when the rate of change in one direction is equal to the rate of change in the other direction. Or when the energy that flows into a system is equal to the energy that flows out of a system. For example, water in a tank may appear at the same level when the rate at which water is added to the tank is equal to the rate at which water is removed from the tank.
WHAT ARE SCIENCE AND ENGINEERING PRACTICES?
Science and Engineering Practices are the behaviors scientists and engineers exhibit when engaged in science or engineering. For instance, scientists usually ask questions that can be investigated through experiments, while engineers ask questions that can be solved by engineering solutions. Science and engineering practices include:
Asking Questions and Defining Problems
Scientists ask questions about natural phenomena that can be tested by experiments. The results of successful experiments usually help scientists describe and explain how a phenomenon works. For example, in the past, scientists had observed that when chemicals react their masses remained unchanged before and after the reaction (law of conservation of mass). This observation led Dalton to propose the atomic theory to explain the law of conservation of mass.
Developing and Using Models
Scientists construct models to help represent and explain their ideas. The models they construct include diagrams, drawings, mathematical formulas, and computer simulations.
Planning and Investigating problems
Scientists plan and investigate phenomena in the field or laboratory setting. Usually scientists can work together or alone to investigate phenomena.
Analyzing and Interpreting Data
Scientists use tools such as tables, graphs, simulations, and statistics to analyze data to identify patterns and trends. They then try to generate explanations for these patterns and trends.
Using Mathematics and Computational Thinking
Scientists and engineers apply mathematics in science. Mathematics is used to represent relationships between variables. These relationships are usually used to construct simulations and statistical analysis.
Constructing Explanations and Designing Solutions
Scientists construct explanations and engineers apply these explanations to design engineering solutions to problems.
Using Evidence to Argue
Scientists use empirical evidence to argue so that they can generate logical explanations and solutions to problems.
Obtaining, Evaluating, and Communicating Information
Scientists must have the ability to obtain, evaluate, and communicate their results and research methods to their peers at conferences and professional meetings.
NATURE OF SCIENCE
If we integrate the three-dimensions of the NGSS, the nature of science emerges. We can visually illustrate this as:
WHAT’S THE NATURE OF SCIENCE?
Science is a way of knowing or gaining knowledge about our world. Scientists usually follow a set of guidelines to investigate a problem. Some of these guidelines are that: scientific explanations must be
- supported with data
- supported by other scientists or the scientific community
- consistent with what is already known
How do scientists obtain data to support their ideas?
Scientists obtain data by observing the world around them. They observe by using their senses to get information about phenomena. Sometimes, however, their senses may be limited by what they can observe. As a result, scientists usually rely on technology to enhance and extend their senses so that they can closely study molecular processes. For scientific observations to be credible, they must meet certain requirements. These requirements include:
- scientific observations must be made under controlled conditions. Control conditions means to control the things that could possible affect the results of an experiment. When scientists investigate a phenomenon, other scientists usually assume that they are aware of the things that could possibly affect the results, and that they have taken the necessary steps to keep those conditions the same. Another name for making observations under controlled conditions is called an experiment. Experiments are common in research studies. As a result, you sometimes hear control or experiment (treatment) group when scientists report their research studies.
- scientific observations must be Repeatable. Repeatable means another or the same scientist can use identical or similar methods to replicate the experimental results. If the experiment’s results can’t be repeated, then they can’t be credible. And if results aren’t credible, it usually means that there are things affecting the experiment the scientists may not have controlled.
- scientific observations may be subject to change in light of new evidence. Technology improves daily so it’s possible that a newly developed technology may provide more insight about a phenomenon than a previously known one. For example, Thomson improved Dalton’s atomic theory by using cathode ray tube to explore the structure of an atom. Rutherford also improved Thomson’s atomic theory by using the gold foil experiment to explore the structure of an atom.
- scientific observations are facts based on experiments and observations (empirical evidence). For example, we have all observed that when an object is thrown up, the earth’s gravitational force pulls it back to the ground.
You can learn more about the Next Generation Science Standards at NSTA
