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

Globally, precipitation far exceeds evaporation.

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Module of the day


This module introduces the concept of evolutionary adaptation. It follows the development of Charles Darwin's ideas on how species adapt to…

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Term of the day


[noun] A clear, water-based gel that contains enzymes, salts, and organic molecules. In eukaryotic cells, cytoplasm surrounds the nucleus and organelles. The…

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