A learning space for science educators and students

Free Award-winning Content
Free Award-winning Content

We create and provide high-quality, accessible, educational content in the science, technology, engineering and mathematics (STEM) disciplines at the introductory undergraduate level.

About us
Next Generation Science Standards
We support NGSS

Our exclusive content integrates science and engineering practices with disciplinary core ideas and cross-cutting concepts in alignment with the Next Generation Science Standards.

About NGSS

Quick Quiz

Density is defined as

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Module of the day


In the field of molecular biology, scientists examine how DNA encodes all the complexities of living things. This third module in…

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Term of the day


[verb] The breaking apart of a molecule, especially in the presence of heat or a polar solvent. For example, the ionic…

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