Background Information

The Next Generation Science Standards (NGSS) were written by 41 writers from 26 lead states in a process managed by Achieve Inc. They are based on the National Research Council’s A Framework for K-12 Science Education. The NGSS consist of performance expectations, foundation boxes, and connection boxes. The performance expectations in NGSS are grouped together in two different arrangements:

  • According to topics that the writers used when writing the performance expectations
  • According to disciplinary core ideas from the NRC’s Framework for K–12 Science Education

Both versions use the same coding system, which is based on the disciplinary core ideas. States have an option of using either arrangement when they adopt the standards or developing their own arrangement.

For more information, see How to Read the Standards, the Front Matter, Commonly Used Abbreviations,
Why Standards Matter, and Public Attitudes Toward Science Standards.

The official version of the standards can be found at


Supporting Documents

  • Three Dimensions of NGSS (Color | B&W)
  • Inside the NGSS Box Diagram (Color | B&W)


Venn Diagrams (Developed by Understanding Language at Stanford University)