Everything about money and choices: study cards, the traps to dodge, a practice quiz at three levels — Foundation, On-Level, and Challenge — and a lab where you sort goods from services and needs from wants, graph a $20 budget, and argue a choice with its opportunity cost. Work here, or print it and use a pencil — both count.
You have five dollars, and two things you want. The book and the movie ticket both cost five.
Every yes is a no to something else. Opportunity cost is the THING you gave up — the movie — not the money you spent. When a question asks what a choice cost, name the other option, not the price tag.
Two things people get wrong
⚠️People often think…
Opportunity cost is how much money you spent.
It is the THING you gave up. If you spend Saturday at a job, the opportunity cost is the game you missed, not the hours. Naming the money misses the whole idea.
Name the thing, not the price.
⚠️People often think…
A business that took in a lot of money made a lot of profit.
Income is not profit. Subtract the costs first — supplies, rent, help. A lemonade stand that took in $40 and spent $35 on lemons and cups made five dollars, not forty.
Profit is income minus costs.
Worth knowing cold
Four words that trip people up
Each one has a short test you can actually apply in your head.
Good / serviceA GOOD goes in a bag — a sandwich, a bike. A SERVICE is work someone does for you — a haircut, a bus ride. Can you hold it?
Need / wantA need keeps you alive and safe; a want is everything after that. The first coat is a need; the second is a want.
Income / profitIncome is what came IN. Profit is what is LEFT after the costs. A stand that took in $40 and spent $35 made $5.
Scarce / plentifulScarce AND wanted pushes a price up. Plentiful pushes it down. Both halves matter — something rare that nobody wants stays cheap.
Make, earn, plan, spend, save, choose
1Watch one
A lemonade stand takes in $40 and spends $35. How much did it make?
Write down the income: $40 came in.
Write down the costs: $35 went out for lemons, sugar and cups.
Profit is income MINUS costs, so 40 − 35.
$5. The stand was busy all day and kept five dollars — that is why costs matter. ✓
2Do one with me
Fill in the words.
A haircut is a
Income minus costs is called
When something is scarce AND wanted, the price goes
💬One sentence, then you move on
Why is opportunity cost the thing and not the money?
3Try one
You already own a warm coat and buy a second one. Need or want?
I want a hint first
You already have a coat that works. What does the second one keep you safe from?
Where this goes
Where this lives
Deciding what to do with allowance or a paycheck, understanding why one store charges more, noticing what you gave up every time you said yes to something.
What this feeds
Next unit is maps and regions of the United States.
Name one choice you made today and what you gave up.
One card at a time — tap “Show me” to check yourself, then Next. Start at Foundation; when those feel easy, climb.
Helpful Hints
🪜 From a job to a choice — the ladder
Producers make goods and services → you earn money by producing → you spend it on needs first, then wants, and save some by a budget → prices tell you what is scarce → and every choice costs you the thing you didn’t choose.
Make, earn, plan, spend, save, choose.
🤝 The whole topic in one idea
There is never enough money or time for everything, so every choice means giving something up. Good choices put needs first, save a little, and know what they cost.
Every yes is a no to something else.
⚠️ Traps the test loves
A good goes in a bag; a service is work someone does for you.
Opportunity cost is the THING you gave up, not the money you spent.
Profit = income minus costs. Income alone is not profit.
Scarce AND wanted makes a price go up. Plenty makes it go down.
The first coat is a need; the second is a want.
A budget has to ADD UP to what you actually have.
💵 Six money words — the chart
Word
Means
Example
income
money you earn
$20 from mowing lawns
costs
what you pay to make or do something
$6 of lemons and cups
profit
income minus costs
$20 − $6 = $14
budget
a plan that adds up
$9 need, $5 save, $6 wants
interest
extra a bank pays you for saving
$100 becomes $103
opportunity cost
the thing you gave up
the game, when you bought the book
Earn, pay, keep, plan, grow, give up.
🎯 How the test will ask
A list of items — “good or service?” “need or want?”
A lemonade stand — “what’s the profit?” (income minus costs).
A budget that’s too big — “what do you cut first?” (wants).
Two things you want, money for one — “what’s the opportunity cost?” (the other one).
✅ Before the test, can you…
Sort ten items into goods and services?
Tell a need from a want with the ‘could I live safely without it’ test?
Make a $20 budget that adds up, needs first?
Find a lemonade stand’s profit?
Name the opportunity cost of a choice you made this week?
Pick your level
Look back at anything you missed — the hint that appeared is exactly what to reread tonight.
How sure did you feel?
Workshop
Work like an economist: tell a good from a service, sort needs from wants, graph a $20 budget, then make a claim you can back.
Your practice never leaves this device. There is no account and no sign-in. Your work is saved in this browser only, and you can erase it whenever you want.
Your practice record — saved on this device
This is your record of the module on screen — it stays here and goes nowhere. Independent means you got it right on the first tap; supported means you got it after the explain-and-retry, or marked ‘I had it’ on a revealed answer. Both count, and neither is a grade. If your teacher asks, copy the row or show them this screen.
Date
—
Topic
—
Level
—
Independent
0 of 0
Supported
0 of 0
Hints used
0
Cards studied
0
Lab
—
Traps met
0
Explained in own words
0
Confidence
—
The answer key is for a teacher: it prints only from here, for the unit on screen. Print the study packet prints the study pages and a blank quiz — never the answers.