Four places to start
Start a course today — completely free.
Numbers, money, reasoning, and running something of your own — each a path of short lessons that builds level by level. Open any course below and take your first lesson right now: no fees, no account needed.
- Pre-K to university38 levelsFree
Mathematics
From counting and comparing to algebra, calculus, probability, and university analysis. The longest path on the platform, and the foundation under the other three.
- Early mathematics A — Mathematics (opens in a new tab)Pre-K
- Fractions, level 3 — Mathematics (opens in a new tab)Around grade 3
- Mathematics level 7 — Mathematics (opens in a new tab)Around grade 7
- Algebra I — Mathematics (opens in a new tab)Secondary
- Statistics and probability — Mathematics (opens in a new tab)Secondary
- Calculus BC — Mathematics (opens in a new tab)Secondary
- Money and choices7 levelsFree
Economics
Why there is never enough of everything, and what people do about it: scarcity and trade-offs, markets and prices, up to intermediate micro- and macroeconomics.
- Wanting more than there is — Economics (opens in a new tab)Around grade 3
- Scarcity, choice and trade-offs — Economics (opens in a new tab)Around grade 6
- Markets, prices and money — Economics (opens in a new tab)Around grade 8
- Microeconomics — Economics (opens in a new tab)Advanced
- Macroeconomics — Economics (opens in a new tab)Advanced
- Intermediate economics — Economics (opens in a new tab)Advanced
- Thinking clearly8 levelsFree
Logic & Philosophy
How to tell a good reason from a bad one. Claims and arguments, weighing evidence, formal and symbolic logic, then ethics, knowledge, and the mind.
- Reasons and claims — Logic & Philosophy (opens in a new tab)Around grade 5
- Arguments in the wild — Logic & Philosophy (opens in a new tab)Around grade 7
- Reasoning about evidence — Logic & Philosophy (opens in a new tab)Around grade 8
- Formal logic — Logic & Philosophy (opens in a new tab)Advanced
- Ethics — Logic & Philosophy (opens in a new tab)Advanced
- Mind and metaphysics — Logic & Philosophy (opens in a new tab)Advanced
- For people running one5 levelsFree
Small Business
The practical side of keeping a small business alive: costs, pricing and break-even, cash, customers and sales, operations and people, strategy and risk.
- Costs, pricing and break-even — Small Business (opens in a new tab)
- Money, costing and cash — Small Business (opens in a new tab)
- Customers and sales — Small Business (opens in a new tab)
- Operations and people — Small Business (opens in a new tab)
- Strategy, growth and resilience — Small Business (opens in a new tab)
And more
More subjects, all of them free.
The same step-by-step lessons reach into the sciences, history, geography, study skills, and test prep for the GRE, LSAT and GMAT. Every subject is free.
- History2 levelsThe past and how we know it (opens in a new tab)
- Geography8 levelsMaps, places and Earth systems (opens in a new tab)
- Physics11 levelsMeasurement to modern physics (opens in a new tab)
- Chemistry5 levelsMatter and change (opens in a new tab)
- Astronomy4 levelsStars, galaxies and cosmology (opens in a new tab)
- Memory & Cognitive Skills8 levelsStudy skills and memory (opens in a new tab)
- GRE9 levelsGraduate school test prep (opens in a new tab)
- LSAT8 levelsLaw school test prep (opens in a new tab)
- GMAT9 levelsBusiness school test prep (opens in a new tab)
GRE, LSAT and GMAT courses are independent preparation, not affiliated with the organizations that run those tests.
Explore all subjects(opens in a new tab)Free books
Take the course. Then read the book.
Nydus Foundation also runs a free Library of classic books. Read them in your browser, download them, or print them, with no account and no email. Here are a few to start with.
- LiteratureAlice’s Adventures in WonderlandLewis Carroll (opens in a new tab)
- PhilosophyMeditationsMarcus Aurelius (opens in a new tab)
- PhilosophyThe PrinceNiccolò Machiavelli (opens in a new tab)
- PhilosophyThe Art of WarSun Tzu (opens in a new tab)
- LiteratureThe Great GatsbyF. Scott Fitzgerald (opens in a new tab)
- LiteratureFrankensteinMary Shelley (opens in a new tab)