Teaching Models

Using Money

When finding the value of a collection of pennies, simple counting is used and the result gives us the value of the collection of pennies. When finding the value of a collection of nickels, skip counting by 5s can be used to find the total value. A collection of dimes would be skip counted by 10s, and a collection of quarters would be skip counted by 25s.

To find the value of a collection of coins of different values, children should start with the greatest-value coin, go to the next value, and so on. For example, if a collection consists of 1 half-dollar, 1 quarter, 1 dime, 2 nickels, and 3 pennies, one could start with 50 and count on as follows:

half dollar quarter dime nickel nickel penny penny penny
50¢ 75¢ 85¢ 90¢ 95¢ 96¢ 97¢ 98¢

So the value of this collection is 98¢.

An important step in studying money is to reach the amount of 1 dollar. At this point a transition is made from a whole-number notation to a decimal notation: 100¢ = $1.00.

Counting on is a strategy for making change. If an item costs 37¢ and a half-dollar is used to pay for the item, then one would count on from 37¢ to 50¢.

37 — penny 38, penny 39, penny 40, dime —   50.

Note that, in this strategy, the amount of change is not calculated. To find the amount of change received, count on to conclude that the change received is 13¢.

dime 10   — penny 11   — penny 12   — penny 13

Teaching Model 15.3: Use the Fewest Coins

Houghton Mifflin Math Grade 2