🖍️a chalk mark: one bun📝an I O U note🥖a bun now, paid on Friday
Ways to pay later.
The big ideaA tab or an IOU is a written promise to pay later. It runs on trust.
How it works
Long ago, before cards, Rosa the baker let Sam take buns now and pay on Friday. Each bun cost 1 pretend coin.
Rosa made a chalk mark on a board for each bun. A list of what we took and have not paid for yet is called a tab.
Sam also wrote an I O U, a note that says I owe you. It is a promise written down.
Paying later works only because people trust each other.
Sam's tab, a bun for each mark.How the tab was paid.
Example 1: Add the tab
Sam took 2 buns on Monday, 1 on Tuesday and 3 on Wednesday.
2 + 1 + 3 = 6
Six buns at 1 coin each is 6 coins owed.
Example 2: Write the I O U
The note says: I owe you six coins.
Sam drew six coins on it too, so it was easy to read.
Sam signed it with a curly name.
Example 3: Pay the tab
On Friday Sam earned 6 coins carrying baskets.
Rosa counted exactly 6 coins.
6 − 6 = 0
Nothing is owed now, so Rosa rubbed out the chalk marks and handed back the note.
Example 4: Now or later
Coins handed over at the counter pay at once.
A chalk mark on a tab waits to be paid.
A bun taken Monday and paid Friday waits to be paid.
Words to know
tab
A list of what we took and have not paid for yet.
I O U
A note that says I owe you.
owe
Must pay those coins back.
trust
Believing someone will do what they promised.
Watch out
I O U means I owe you. It does not mean I paid you.
A bun on a tab is not free. It is owed.
Count every day's buns: 2 + 1 + 3 = 6, not 5.
A tab only works when the one who waits can trust you.
Try it
Sam took 2 buns on Monday, 1 on Tuesday and 3 on Wednesday. How many coins does he owe?
What does I O U mean?
Coins at the counter or a chalk mark on a tab: which pays right away?
Answers: 1. 6 coins · 2. I owe you · 3. Coins at the counter
Try at homeWith a grown-up, write a pretend note that says I owe you, for something small. Sign it, and tear it up when it is paid.
For grown-upsWith your child, write a pretend I O U for something small, sign it, and tear it up when it is paid. It shows that paying later is a promise and that it runs on trust. Pretend coins are enough.
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