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

Earth's magnetic field is constant.

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Module of the day

Nuclear Chemistry

Beginning with the work of Marie Curie and others, this module traces the development of nuclear chemistry. It describes different types…

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Term of the day


[noun] The collective mass of gases that surrounds the Earth or another planet.

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