Money · 222 lessons in the app
The rule of 72, paying yourself first, why inflation works like a tax. These are general lessons on how people think about money. For a full personal finance course with your country's tax rules, see our sister app, Scroll: Learn Personal Finance.
Lesson 1 of 4
Divide 72 by your annual return rate to find how many years it takes to double your money. 72 ÷ 8% = 9 years to double. 72 ÷ 6% = 12 years. Works for debt too, a 24% credit card interest rate doubles your debt every 3 years. Quick, powerful, and requires no calculator.
Source Pacioli, L. (1494). Summa de arithmetica.
Quick quiz
Using the Rule of 72, how long does it take to double your money at an 8% annual return?
Lesson 2 of 4
Most people save what's left after spending. Wealthy people spend what's left after saving. The solution is automatic: on payday, transfer a fixed percentage to savings before you can spend it. You won't miss what you never see. This single habit has created more millionaires than any investment strategy.
Source Clason, G.S. (1926). The Richest Man in Babylon.
Quick quiz
What is the key principle behind 'pay yourself first'?
Lesson 3 of 4
A dollar today buys less than it did 10 years ago. Inflation erodes purchasing power silently and constantly. Cash sitting in a bank account at 0.1% interest while inflation runs at 3% loses 2.9% real value per year. Not investing isn't "safe". It's a guaranteed slow loss.
Source Federal Reserve (2023). Understanding Inflation.
Quick quiz
Why is keeping cash in a 0.1% savings account during 3% inflation not 'safe'?
Lesson 4 of 4
People treat money differently based on where it came from or where it's going, even though money is fungible. A tax refund feels like 'bonus money' and gets spent frivolously, even though it's the same money you earned. Casino winnings feel like 'house money.' This mental accounting leads to irrational financial decisions across the board.
Source Thaler, R. (1985). Mental Accounting and Consumer Choice. Marketing Science.
Quick quiz
What is 'mental accounting' and how does it affect financial decisions?
Every title here is a lesson in Scroll, with its own quiz. Five a day are free; Premium has no daily limit.
No. The money lessons explain general ideas with worked numbers. They don't know your circumstances, so they can't tell you what to do with your money.
Scroll's sister app, Scroll: Learn Personal Finance, has 950+ money lessons set up for your country's rules, plus free calculators at scrollfinance.app.
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