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Understand money. From the very first coin.
Solidus is a calm, complete course for people who never learned how money works. Start from zero, move at your own pace, and prove what you know with a short quiz after every lesson.
How Solidus works
- 1
Choose your level
Start from the beginning, or take a placement test and skip what you already know.
- 2
Read short lessons
Plain language, worked examples, and notes on how things differ between countries.
- 3
Pass the quiz
Each lesson ends with a quiz that is meant to make you think. Score 80% to unlock the next lesson.
- 4
Play with the tools
Calculators for compounding, inflation, loans and more, whenever you want to try an idea.
One path, from coins to the global economy
Every module builds on the one before it. Already know a topic? Pass its test and move on.
Level 1
Foundations
Level 2
Everyday money
Level 3
Borrowing
Level 4
Protecting and growing
Level 5
The long term and the big picture
Level 6
Around the world
Why a gold coin from the year 309?
The solidus kept its value for seven centuries. Its 72 beads, its slash and its laurel each tell part of what we teach.
Read the story of the emblem