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 chemistry using videos, articles, and NGSS-aligned practice exercises. Explore the world of elements, compounds, and mixtures, learn about the periodic table, understand physical properties …

Explore middle school biology topics with Khan Academy's free, world-class educational resources.

In this high school physics course, we'll answer all these questions and many more. Physics is the science of building models to explain how the universe works. We take observations, describe them …

Unlock the exciting world of chemical reactions! Learn to identify chemical properties and changes that create entirely new substances, decode chemical equations and master the art of balancing them, …

Learn how to describe the position, velocity, speed, and acceleration of an object. Explore how motion can be represented using words, diagrams, data tables, and graphs. Distinguish between constant …

Learn physics using videos, articles, and NGSS-aligned practice exercises. Explore the fundamentals of motion and forces, non-contact interactions, energy, and waves.

Explore high school physics topics including forces, motion, energy, electromagnetism, and light, from stars to subatomic particles.

Oops. Something went wrong. Please try again. Uh oh, it looks like we ran into an error. You need to refresh. If this problem persists, tell us.