What your money decisions cost you
Seven modules, about eleven hours, ending in a simulation that plays out seventy years of your financial life. Free, no sign in, and nothing is uploaded: once a page has loaded it runs entirely on your own machine.
The modules
They are built to run in order. Each one gives you the vocabulary the next one assumes, and all five of the ideas from Modules 1 through 5 show up together in the simulation at the end.
Every module part is built to fit a class period, so the longer ones are split in two with a stopping point between them. The simulation is the exception: it runs two to three hours, or one period on the shorter run. All together that is about eleven hours, or twelve to fourteen fifty-minute periods. The times below assume you attempt the questions rather than reading past them.
Why your choices matter
Opportunity cost. Estimate what a purchase costs you across twenty years, then work seven problems until you can do it without a calculator.
Ready, about 45 minutesUsing it on real decisions
Build the cost of a degree from your own figures, and find where the arithmetic stops being able to decide for you.
Ready, about 45 minutesCompounding and time
Where growth actually comes from, why the curve bends, and how long it takes before the growth outweighs everything you paid in. Opens with three questions carried forward from Module 1.
Ready, about 45 minutesThe same machine in reverse
Debt compounds with identical arithmetic. What the minimum payment really costs, the payment below which no debt ever clears, and what the after-inflation shortcut has been hiding.
Ready, about 45 minutesAn average is not a promise
Why the average return you are quoted is not the return you get, and why the order returns arrive in matters enormously to some people and not at all to others.
Ready, about 45 minutesThe illusion of safety
Why cash is not the safe option it looks like, what mixing holdings actually buys you, and why selling after a fall is a plan that loses money when executed perfectly.
Ready, about 45 minutesManaging risk
The other kind of risk: not the movement you take on for a return, but the loss you pay to be rid of. What cover is actually buying, the deductible trade, and the part of your pay you never see.
Ready, about 45 minutesWhat education does to earnings
Measured earnings by education level, what those figures can and cannot settle, and the age at which a path catches what it cost to take.
Ready, about 45 minutesPaths and what closes off
Why the same decision costs more the later you make it, the last age a path still pays for itself, and how to tell a decision that is expensive to reverse from one that only feels that way.
Ready, about 45 minutesThe life simulation
Seventy years, thirty decisions, one run. Everything from the first five modules put back together and made to run, with an outcome you have to live with.
Ready, two to three hoursEvery trap promises to skip the time
Gambling, betting and the arithmetic of a shortcut. What the promise costs, and how to work it out before you decide.
Ready, about 40 minutesReading the claim
The costs nobody is hiding, the loans nobody is breaking the law to sell you, and a true article that still points you the wrong way. It ends by turning the same test on this course.
Ready, about 50 minutesIf you are teaching this
Everything below is free, needs no account, and installs nothing. There is no data protection agreement to sign because there is nothing to protect: no student work leaves the machine it was typed on.
Running it with a class
How long each part takes, how to put thirty students on the same life, how to collect results without anything being uploaded, and a four-point scale for the written answers.
FreeSlides
Twenty-five slides for the whole course, with speaker notes. Every figure is computed from the same model your students use, so you cannot present a number the course no longer believes.
FreeAnswer keys
Every auto-marked question with its answer and the reasoning behind it, read from the students' own pages when you open them rather than typed into a document that could go stale.
FreePlanning guide
What to cut when a period runs short, what students reliably get wrong, which parts a substitute can run cold, and what the first ten minutes should cover.
FreeHow the numbers are checked
Every model here is verified before it is published, against a closed form, an independent second implementation, or an accounting identity. The model checks page runs those tests in your browser and prints READY only when all of them pass. It also measures every text and background color pair against WCAG AA in both light and dark themes, because contrast is something to measure rather than judge by eye.
Each model also states what it leaves out. A calculator that answers confidently outside its own domain is worse than one that declines.
What this collects
Nothing. There is no account, no analytics, and no server to send anything to. Your calculator entries and written answers are saved in your own browser's local storage, which means they stay on the device you typed them on and disappear if you clear your browsing data.
Practically, that has one consequence worth knowing: progress does not follow you between a school computer and a phone. That is a deliberate trade for not asking a student to create an account.