What Is Three-Dimensional Learning and How Does It Relate to NGSS?

Science is the joyful exploration and discovery of the marvels of our universe and the rules by which it operates. But what IS science?

Science has always meant different things to different people at different times in different contexts. If we want our students to understand science, we need to give them the opportunity to experience the joy of science the way that scientists do — by exploring the many different dimensions of science through three-dimensional learning.

What Is Three-Dimensional Learning?

Three-dimensional learning is part of the framework presented by the National Research Council in 2012 that provides an evidence base for the Next Generation Science Standards (NGSS). The NRC Framework defines the three dimensions as:

1. Science and Engineering Practices (SEPs) — these describe what scientists and engineers do, such as asking questions, developing models, analyzing data, and constructing explanations.
2. Crosscutting Concepts (CCCs) — these are overarching themes that connect different scientific disciplines, like patterns, cause and effect, and systems thinking.
3. Disciplinary Core Ideas (DCIs) — these are fundamental scientific concepts within life, physical, and earth/space sciences, as well as engineering.

Together, these dimensions encourage students to engage actively in science as a set of processes and not just a body of facts to be memorized (NRC, 2012).

Examples of How the Three Dimensions Work Together

Primarily, science is a set of action verbs; it is the actions that you DO, such as investigate, experiment, observe, analyze, model, calculate, collaborate, communicate, debate, and defend. These represent the first dimension: Science and Engineering Practices, or SEPs.

Science is also a set of concepts that help to guide you in all of that doing; concepts that provide a framework both for understanding the universe and for setting out to investigate it. These are broad concepts such as form and function, cause and effect, stability and change, and patterns. These represent the second dimension: Crosscutting Concepts, or CCCs.

Then, there is the body of knowledge that has come about from all of that investigating; the “stuff” of science. This represents the third dimension: Disciplinary Core Ideas, or DCIs.

The practices of science have discovered a vast amount of information that is understood to varying degrees. Countless hypotheses are continually thrown up against it to see what sticks. These hypotheses are hotly debated in scientific conferences and journals, and most of them fail and fade away, replaced by newer and better ones. But occasionally one of them holds up and is supported by observations and experiments and becomes part of our core scientific understanding.

If your only exposure to science was to go to a scientific conference and see the passionate debates over cutting-edge scientific discoveries you might mistakenly think that scientists can’t agree on anything, or even that they don’t really know much of anything. Far from it.

What you wouldn’t be seeing is the deep foundation of scientific core ideas, shared by all of the scientific debaters, upon which all of the scientific debates rest. It would be like looking at Earth from space, seeing the churning oceans, clouds, and constantly shifting land vegetation and thinking that it was like this all the way down to its core when, in fact, this geologic chaos is just a surface veneer that is underlain by a deep foundation of thousands of kilometers of solid rock.

So, standards of science education need to make sure that students have the opportunity to develop an understanding of each of these three dimensions of science: the practices of science, the broad overlying concepts of science, and the core ideas of the body of knowledge

The Evolution of Three-Dimensional Learning

Perhaps the most significant single advance of the NGSS over previous standards was that each of the NGSS Performance Expectations (PEs), which are what are commonly referred to as “the standards,” weave together the three dimensions (SEPs, CCCs, and DPIs) in such a way that you cannot assess students on any one dimension.

Because of the way that the NGSS PEs are worded, you can’t just pull out the science “facts” and assess students’ memorization and recall with simplistic multiple-choice tests, as had largely been done before in most states. The three dimensions have to be taught together.

For example, prior to the 2011 Framework for K-12 Science Education, the most influential U.S. educational document was the 1996 National Science Education Standards (NSES), also released by the National Research Council. Most of the pedagogical recommendations that were written into the 2011 Framework had already been in the 1996 NSES report 15 years earlier.

However, all of the various NSES standards — for the science content, practices, crosscutting themes, and even for educational systems, professional development, and assessments — were all in separate chapters, separate from each other (NRC, 1996).

About two-thirds of U.S. states went on to revise their state science standards based on the 1996 NSES. The other third of U.S. states revised their science standards based on the 1993 Benchmarks for Science Literacy report and associated 1989 Science for All Americans report by the American Association for the Advancement of Science, which both came out of the AAAS Project 2061 program (AAAS, 1989; AAAS, 1993).

Most states, though, went into these standards, picked out the science “content,” and left the rest behind. As a result, state science standards largely ended up as lists of facts for students to memorize and be assessed on with multiple-choice tests of memory recall, devoid of the practices of actually doing science.

The Power of the Performance Expectations

This is the brilliance of the NGSS: the science and engineering content, the practices, and big crosscutting themes are woven together into PEs in such a way that no one part could be pulled away from the others. All three dimensions are considered in the design of PE assessments.

For example, one high school physical science PE assessment (HS-PS3-3) is: “Students who demonstrate understanding can design, build, and refine a device that works within given constraints to convert one form of energy into another form of energy.” There is plenty of scientific content here about the conservation of energy, but you can’t assess students using a multiple-choice test in this example because the assessment needs to have them “design, build, and refine a device.” They have to do the science and engineering, and not just know about it, in order to pass the assessment.

In the NGSS, all three dimensions are scaffolded into elements that progress across a student’s full educational experience, K–12. The grade-band benchmarks for the science and engineering content (DCIs) were presented in the NRC Framework, and the NGSS goes on to provide the grade-band benchmarks for both the eight SEPs and seven CCCs, increasing in sophistication with increasing grade level.

The Goals of the Three Dimensions

The goal of the DCIs was to provide students with a subset of core ideas that are both foundational to science and relevant to their own lives. This means that, for example, memorizing the names of minerals, the stages of mitosis, or the types of machines is not as important as understanding how and where minerals form, how evolution works, and how the conservation of energy applies to machines.

The goal for the SEPs was to give students ample opportunity to experience the practices of science (and engineering) the way that scientists themselves do, recognizing that there is not (and never has been) a single “scientific method” but rather a diverse suite of practices with half aligning well with math standards (developing and using models; planning and carrying out investigations; analyzing and interpreting data; using mathematics and computational thinking) and half aligning well with English language standards (asking question and defining problems; constructing explanations and designing solutions; engaging in argument from evidence; obtaining, evaluating, and communicating information). Students should be given multiple opportunities to practice all eight SEPs within each year.

The most challenging aspect of the three dimensions has been the implementation of the seven Crosscutting Concepts (CCCs). These big-picture themes, such as cause and effect, structure and function, and patterns, carry across all of science and build within a student’s educational experience.

For example, much of science operates as part of integrated systems (e.g., the solar system, circulatory system, electrical system) that involve a flow of energy and cycling of matter. As a result, three of the seven CCCs focus on systems (system models, energy and matter within systems, stability and change within systems). Curricula should never include distinct units on the CCCs; rather, student understanding of the CCCs builds over time with multiple reinforcements from carrying out investigations in different fields.

Three-Dimensional Learning Is for Everyone, Not Just Scientists

It doesn’t matter if a student doesn’t plan on becoming a scientist or engineer, they will still benefit greatly from learning these three dimensions. Students will need to make many decisions in their lives that are directly impacted by science and engineering – where they live, the food they eat, the things they buy, the jobs they choose. Students will also be faced with many choices during elections directly related to science and engineering and need to be STEM-literate to be good voting citizens.

And science is cool! Understanding not only how the universe operates but how scientists explore and discover it provides deep aesthetic satisfaction, as shown by the wide popularity of scientific television programming.

However, if students think they do want to go on becoming scientists or engineers, it is crucial that we provide them with the opportunity to learn to think the way that scientists and engineers do, and learning with these three dimensions woven together is the best way to do it.

You Might Also Be Interested In …

• BLOG: What Are Next Generation Science Standards (NGSS)?
• PODCASTS: Keepin’ Science Real Series
• FREE ACTIVITY: The Pencil Challenge

References

• American Association for the Advancement of Science. (1989). Science for All Americans. Project 2061. New York: Oxford University Press. Available: http://www.project2061.org/publications/sfaa/online/sfaatoc.htm
• American Association for the Advancement of Science (1993). Benchmarks for science literacy. Project 2061. New York: Oxford University Press.
• National Research Council (2012). A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas. Washington, DC: The National Academies Press. https://doi.org/10.17226/13165
• National Research Council (1996). National Science Education Standards. Washington, DC: The National Academies Press. https://doi.org/10.17226/4962
• National Research Council (2013), Next Generation Science Standards: For States, By States. Washington, DC: The National Academies Press. https://doi.org/10.17226/18290