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.

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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

Energy Metabolism II

ATP is the main energy currency of living cells. This module answers the question of how most ATP is generated. A…

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Term of the day


[noun] One of fewer than 118 pure chemical substances. An element is a substance composed of atoms with identical atomic number.

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