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

Cellular Organelles I

Evolution isn't always about competition. It can also be about cooperation, as is the case with the development of chloroplasts and…

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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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