Best Sites to Find Study Materials by Subject

Finding reliable and well-organized study materials can greatly enhance a student’s academic success. Thankfully, a number of websites provide high-quality, subject-specific resources that are free and accessible to learners worldwide. Whether you’re looking to brush up on math formulas, study for a science test, or improve your writing skills, the following platforms can guide you to the right content for your subject needs.

1. Khan Academy – Ideal for math, science, history, economics, and grammar. Offers structured video lessons, quizzes, and progress tracking for learners from elementary through college-level. The platform includes mastery challenges, personalized dashboards, and unit tests that help solidify understanding across subjects.
2. CK-12 Foundation – Specializes in STEM subjects. Provides digital textbooks, simulations, and practice exercises for K–12 students in math, science, and engineering. Its FlexBooks and adaptive practice tools help accommodate different learning speeds and styles.
3. CrashCourse (YouTube) – Great for history, biology, literature, chemistry, psychology, and social studies. Offers fast-paced, animated videos that explain complex topics in an engaging and humorous way. Ideal for high school and early college learners.
4. Coursera (Audit Mode) – Access free course materials from universities in a wide range of subjects like psychology, business, data science, and computer programming. Ideal for high school, college, and adult learners preparing for academic or career advancement.
5. edX – Features university-level content in humanities, sciences, math, and more. Students can audit most courses for free and explore subject matter from top-tier institutions such as MIT, Harvard, and Oxford. edX also offers MicroBachelors and AP prep courses.
6. Quizlet – Allows users to create and find flashcard sets for nearly every academic subject. Offers features like test mode, matching games, diagram-based review, and spaced repetition to boost memorization. Used widely by both students and teachers.
7. OpenStax – Provides peer-reviewed, openly licensed college textbooks in subjects like physics, chemistry, biology, sociology, economics, and math. Their materials are high quality, easy to navigate, and completely free for students.
8. National Geographic Education – Excellent for geography, environmental science, anthropology, and world cultures. Offers maps, infographics, educational videos, and interactive classroom tools for K–12 and homeschool students.
9. MIT OpenCourseWare – Hosts full-length undergraduate and graduate-level courses in subjects like calculus, biology, computer science, and mechanical engineering. Includes video lectures, problem sets, and exams from real MIT courses.
10. Project Gutenberg – Best for literature and reading comprehension. Offers over 60,000 free classic books and literary works, including novels, poems, plays, and historical texts. A great tool for English and literature students.
11. ReadTheory – Supports reading and language arts with grade-leveled comprehension passages and quizzes. The platform adapts to student performance and provides detailed feedback and reading insights.
12. Paul’s Online Math Notes – A trusted resource for high school and college math topics including algebra, calculus, trigonometry, and differential equations. Includes lecture-style notes, worked examples, and practice problems with solutions.
13. BBC Bitesize – Covers a wide range of school subjects for primary and secondary levels in the UK curriculum. Includes English, science, history, math, languages, and computing. Features animations, quizzes, and revision guides.
14. Purdue OWL (Online Writing Lab) – Ideal for writing, grammar, research, and citation help. Offers detailed guides on academic essays, resumes, grammar rules, and citation formats like APA, MLA, and Chicago. Frequently used by high school and college students.
15. Saylor Academy – Offers full free courses in subjects like history, business, political science, and philosophy. Each course includes structured readings, assessments, and a certificate of completion. Ideal for learners preparing for CLEP exams or pursuing self-study.
16. HippoCampus – Offers free multimedia content across subjects such as algebra, biology, earth science, economics, and government. Includes lessons from NROC, PhET, and other educational providers. Excellent for visual and auditory learners.
17. BioMan Biology – Offers interactive games, quizzes, and virtual labs focused on biology. Topics include genetics, cells, ecology, and evolution. Great for middle and high school biology students who learn through gamification.
18. The Physics Classroom – Provides clear tutorials, concept builders, and interactive simulations covering high school physics topics like motion, energy, waves, and electricity. Also includes ACT/SAT science prep materials.
19. TypingClub – For keyboarding and digital literacy skills. Offers a structured curriculum to teach students typing through interactive lessons and games.
20. Code.org – Great for students interested in computer science. Provides beginner-friendly lessons on coding, logic, algorithms, and app design. Courses range from elementary to high school level.

In summary, finding subject-specific study materials online is easier than ever. These websites support a variety of learning styles and academic levels, from middle school to university. Whether you need a visual explanation, practice quizzes, interactive simulations, or full textbooks, these platforms provide trusted, accessible resources to help you succeed across all areas of study. With so many options available, students can take charge of their learning and explore subjects in depth, at their own pace, and without cost.