Learn science using videos, articles, and TEKS-aligned practice exercises. Review the fundamentals of matter and energy, forces and motion, Earth's systems and processes, living organisms and …

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.

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In AP Physics 1, you'll learn algebra-based classical mechanics. To make sure you’re prepared with the fundamentals, we recommend completing high school physics before diving into AP Physics 1.

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Practice Course Grade 6 Science 5 units · 42 skills Unit 1 Life sciences Unit 2 Chemistry Unit 3 Energy and energy transfer

Learn AP Environmental Science using videos, and AP-aligned practice. Review the fundamentals of ecosystems, biodiversity, populations, earth systems and resources, land and water use, energy …

Chemistry is the study of matter and the changes it undergoes.

For centuries science has told us that it is an invisible epidemic that kills mothers. Causes may be changes in the air or some extraterrestrial influence or a movement of the earth itself, an earthquake.

Practice Apply: synthesis, decomposition, and combustion reactions Get 3 of 4 questions to level up!