## Place Value and Money: When Students Ask

• Why should I learn about place value and money?
Use this question to initiate a class discussion about situations where not knowing much about place value or money would be a problem. Here are a few suggestions.
1. You give a clerk a \$20 bill for a hat that costs \$8.95. The clerk gives you a nickel and a \$1 bill in change. (You are missing \$10.00.)
2. The class that collects the most canned goods for the canned food drive gets a trip to the amusement park. Your class collected 1,547 canned goods. The other fourth-grade class collected 1,457. It's up to you to determine the winner. (1,547>1,457)
• Why do I have to put commas in numbers?
Explain to students that commas are used to separate periods, or groups of three digits in a number. They can use commas to help them read greater numbers. When they see a comma, they say the name of the period.

642,700,391 ---> six hundred forty-two million, seven hundred thousand, three hundred ninety-one

• When I count money, why should I start with the bill or coin of the greatest value?
Give students an example to illustrate that counting money of decreasing value is easier than counting money of increasing value.
• Why do I have to start at the left to compare numbers? Why can't I start at the right?
Point out to students that they compare numbers starting with the greatest place value. The greatest place value is the place on the far left.