Explore science with Khan Academy's free courses, videos, and exercises in physics, chemistry, biology, and more for a world-class education.

Khan Academy offers free, world-class education in various subjects including math, science, and arts, aiming to make learning accessible for everyone globally.

Learn high school chemistry using videos, articles, and NGSS-aligned practice. Explore the fundamentals of atomic structure, chemical bonding, chemical reactions, thermochemistry, solutions, …

Explore advanced computer science topics from algorithms (how we solve common computing problems and measure our solutions' efficiency), to cryptography (how we protect secret information), to …

Learn how to code computer programs, how to design algorithms that make computers more efficient, and discover what a career in computing could look like.

This course builds foundational skills and real-world problem-solving techniques essential for advanced math and science studies.

Hour of code in your classroom The Hour of Code is a global movement by Computer Science Education Week and Code.org reaching tens of millions of students in 180+ countries through a one …

The chemistry archive contains legacy chemistry content, and is not being updated with new content. For our most up-to-date, mastery-enabled courses, check out Middle School Chemistry, High School …

Regardless of who you are, mastering even just one more skill on Khan Academy results in learning gains.

Explore comprehensive Algebra 1 lessons, interactive exercises, and videos to master algebra concepts and enhance problem-solving skills on Khan Academy.