Lesson 9 · Written for kid, teen, and little
Why Prices Go Up and Down
Price is a tug-of-war between how much exists and how many people want it.
Price is where two forces meet: supply, how much of something exists to sell, and demand, how many people want it. When supply shrinks or demand grows, the price tends to rise. When supply grows or demand shrinks, the price tends to fall. This is why the same thing can cost different amounts on different days, and it is the reason stock prices move too. 📈
Words to know
5supply
How much of something there is to buy right now. Like how many bottles of water the shop actually has on the shelf.
demand
How many people want to buy something and are ready to pay for it. On a hot day, demand for cold drinks jumps.
shortage
When people want more of something than there is to go around. Like a sold-out concert where thousands still want tickets.
surplus
When there is more of something than people want to buy. Like the pile of leftover costumes a shop is stuck with in November.
supply shock
A sudden event, like a storm or a strike, that cuts how much of something can be made.
Supply is how much of something exists to buy. Demand is how badly people want it. Swipe true or false.
If lots of buyers want a limited-edition sneaker, the resale price usually goes up.
Swipe the card — or tap.
In the full lesson
- 1True or false
- 2Work out the number
- 3Make the call
Vine has 107 lessons like this one, each written three ways so a 7-year-old and a 17-year-old both get a version that fits.
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- 🏢What is a stock?How owning a share means owning the business.
- 📈Why prices moveNews, demand, and what people believe.
- ❄️Compound interestDrag the sliders to see how time builds wealth.
- 🧺Spreading your betsWhy one bad pick shouldn't sink everything you own.
- ⏳Time in market beats timing itA long-term plan means fewer guesses about when to jump in or out.
- 🛒Needs vs. WantsNeeds keep you okay; wants make life fun — and knowing which is which protects your money.