Learn about all the sciences, from physics, chemistry and biology, to cosmology and astronomy, across hundreds of videos, articles and practice questions.

Unit 1: Intro to biology Welcome to biology! The science of biology Water and life

Created by experts, Khan Academy’s library of trusted, standards-aligned practice and lessons covers math K-12 through early college, grammar, science, history, AP®, SAT®, and more.

Physics the study of matter, motion, energy, and force.

3:57 Conventional current direction Getting started Article Preparing to study electrical engineering on Khan Academy Getting started

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This unit is part of the Biology archive. Browse videos and articles by topic. For our most up-to-date, mastery-enabled courses, check out [High School Biology] …

Learn AP Biology using videos, articles, and AP-aligned multiple choice question practice. Review the fundamentals of biochemistry, cell biology, genetics, evolution, and ecology, and develop scientific …

Key points Ecology is the study of how organisms interact with one another and with their physical environment. The distribution and abundance of organisms on Earth is shaped by both biotic, living …

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