Whether you're a student teacher homeschooler principal adult returning to the classroom after 20 years or a friendly alien trying to get a leg up in earthly biology — Khan Academy's learning library is available to you for free.
- Learn anything for free: Thousands of interactive exercises videos and articles at your fingertips. Study math science economics finance grammar history government politics and much much more.
- Sharpen your skills: Practice exercises quizzes and tests with instant feedback and step-by-step hints. Follow along with what you're learning in school or practice at your own pace.
- Keep learning when you're offline: Bookmark and download your favorite content to watch videos without an internet connection.
- Pick up where you left off: Your learning syncs with khanacademy.org so your progress is always up-to-date.
Learn using videos interactive exercises and in-depth articles in math (arithmetic pre-algebra algebra geometry trigonometry statistics calculus linear algebra) science (biology chemistry physics) economics (microeconomics macroeconomics) humanities (art history civics finance US history US government and politics world history) and more (including computer science principles)!
Khan Academy is a 501(c)(3) nonprofit organization with the mission of providing a free world-class education for anyone anywhere.
Show More >