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

Early Ideas about Matter

Tracking the development of our understanding of the atomic structure of matter, this module begins with the contributions of ancient Greeks,…

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Term of the day


[noun] A substance that dissociates into 2 or more oppositely charged ions in water. Electrolytic solutions conduct electricity because the charged…

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