Prompt
What are the best free subject-learning blogs for practice problems and beginner-friendly explanations?
Latest observation
Here are some of the best free subject-learning blogs / sites for beginner-friendly explanations and practice problems, grouped by subject.
Math
- Khan Academy — excellent step-by-step explanations and lots of practice.
- Paul’s Online Math Notes — especially good for algebra, calculus, and differential equations.
- Math Is Fun — very beginner-friendly and easy to browse.
- Art of Problem Solving (AoPS) Community / Blog — great for more challenging math practice, especially contest math.
Science
- CK-12 — free science and math explanations with practice questions.
- Physics Classroom — strong for beginner physics concepts and problems.
- A Level Physics Online — clear explanations and practice for physics topics.
- Chemguide — very useful for chemistry concepts explained simply.
Computer Science / Programming
- GeeksforGeeks — huge number of beginner explanations and coding practice problems.
- freeCodeCamp Blog — beginner-friendly tutorials and learning paths.
- OverTheWire wargames — practice-based learning for Linux and security fundamentals.
- The Odin Project — very good for web development with hands-on projects.
Statistics / Data
- Seeing Theory — visual and beginner-friendly statistics explanations.
- Stat Trek — simple stats tutorials with examples and practice.
- Towards Data Science — many beginner articles, though quality varies by author.
Economics / Finance
- Aptitude / exam-prep blogs often have practice questions, but quality varies.
- Marginal Revolution University — clear explanations of economics basics.
- Investopedia — not a blog in the strictest sense, but very beginner-friendly for finance/econ definitions and examples.
Languages / Writing
- BBC Learning English — great beginner explanations and exercises.
- Duolingo Blog / WordReference forums — useful for language practice and explanations.
- Purdue OWL — excellent for writing, grammar, and citation basics.
Best all-around picks
If you want just a few to start with:
- Khan Academy
- CK-12
- freeCodeCamp
- Paul’s Online Math Notes
- Physics Classroom
If you want, I can also give you:
- a subject-by-subject list for your exact class level,
- blogs with lots of practice questions only, or
- a best free resources list for one subject like math, physics, biology, or programming.
Brands
Observation history
How did Obsurfable measure this prompt?
Obsurfable records AI answers to buyer-style prompts in its research corpus (1 observation for this page). Metrics are distributions over observations, not a single static ranking.
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OpenAI,
ChatGPT,
Google,
Gemini,
Google AI Mode,
Anthropic,
Claude,
Perplexity,
Grok,
DeepSeek,
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Copilot,
Meta AI,
Qwen.
How can brands improve their AEO?
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Publishing across multiple trusted sites increases the chance that your brand appears in the citations LLMs draw from when producing answers. Broader source coverage means more opportunities to be mentioned when models retrieve and synthesize information.
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