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

Which element is classified as metalloid?

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Module of the day

Chemical Bonding

The millions of different chemical compounds that make up everything on Earth are composed of 118 elements that bond together in…

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Term of the day


[noun] Eukaryotic cells depend on organelles known as centrioles to help organize microtubules during cell reproduction (mitosis and meiosis). The centrioles are…

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