Change is the amount of money returned when you pay more than the price. To find change, subtract the price from the amount paid. For example, if an item costs 63¢ and you pay with a dollar (100¢), the change is 100 − 63 = 37¢. The 'count-up' strategy — counting from the price up to the amount paid — mirrors what cashiers do and avoids subtraction with borrowing for many problems.
Act out store scenarios with play money. Teach both the subtraction method and the count-up method, and let students choose. Limit prices to whole cents and amounts paid to single dollar bills initially. Gradually increase complexity to two-dollar amounts.
Imagine you're buying a pencil that costs 63 cents and you hand the cashier a dollar bill. The cashier owes you back the difference — the amount left over after paying the price. That leftover amount is called change. Making change is just subtraction in a real-world context: start with what you paid, subtract what the item cost, and the result is what comes back to you.
The straightforward method is to subtract: 100¢ − 63¢ = 37¢. You already know how to subtract within 100, so you can apply that skill directly here. The challenge is keeping track of units — cents are cents, and you need to line up the numbers carefully. When you write it out as a subtraction problem, 100 − 63, the answer is 37, so the change is 37 cents.
There's a second method that many cashiers use naturally: counting up. Instead of subtracting, you start at the price and count up to the amount paid. From 63 cents, you might think: "63… add 7 cents to get 70, add 30 cents to get a dollar." The total you added — 7 + 30 = 37 cents — is the change. This method avoids borrowing and feels more natural when you're actually handling coins. Both methods give the same answer; which one you use depends on the numbers.
One mistake to watch for: never subtract the amount paid from the price (63 − 100 doesn't make sense here). Change always flows from the amount paid down to the price, because you gave more than was owed. You can check your work by adding the change back to the price — if you get the amount paid, you're right. 63 + 37 = 100. ✓ This idea of checking subtraction with addition is a habit that will serve you in every math context.