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.

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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

Carbon is a common component of

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Module of the day


The concept of energy has fascinated scientists and philosophers for thousands of years. This module describes early ideas about energy and…

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Term of the day

electron shell

[noun] The orbitals around the nucleus of an atom where electrons reside. Also called electron orbitals and energy levels.

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