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

History of Earth's Atmosphere II

The composition of Earth’s atmosphere has evolved over time. This module examines how Earth came to be the only planet in…

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Term of the day

atomic mass

[noun] The average mass of an atom of an element, usually expressed in atomic mass units. The term is often used interchangeably…

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