Lesson Plan - Get It!
The frog hopped 1.5 feet. If the frog were a math expert and jumped on a number line, where would the decimal number 1.5 be on that number line?
A number written with digits after the decimal point (.) is called a decimal number.
A decimal number is not a whole number. A decimal number is a number that is between two whole numbers and has a decimal point. A number line can help you understand decimal numbers.
First, review placing decimals on a number line with an interactive game and video. Complete the following steps:
- Go to Place Decimal on a Number Line (StudyJams!) and click on the green button labeled STEP BY STEP to watch how to place decimals on a number line. Click on the NEXT and SHOW ME buttons to progress through the steps.
- Click on WATCH OUT! to review how comparing decimals can help you place decimals on a number line.
After you have completed the activity above, discuss the following with a parent or teacher:
- How does the whole number part of a decimal number help determine the location on a number line?
- Explain how place value can help you plot numbers on a number line.
A number line helps you visualize numbers by evenly spacing the numbers on a horizontal line. The decimal numbers increase the farther to the right you move.
On the decimal number line below, there are 10 evenly-spaced sections from 0 to 1. If you start counting at 0, you will count each tenth until you reach “ten tenths,” which is equal to one whole. You can relate money to decimals on a number line by thinking of a dime. A dime is a tenth of a dollar, so ten dimes equal a dollar, or one whole.
Some number lines involve hundredths. There are 10 evenly spaced sections from 0 to 0.1. If you start counting at 0, you will count each hundredth until you reach “ten hundredths,” which is equal to one tenth.
Look at the problem from the beginning of the lesson:
The frog hopped 1.5 feet. Where would the decimal number 1.5 be on a number line?
The decimal number 1.5 has a whole number of 1, which is the number to the left of the decimal. The number 1.5 is halfway between 1 and 2.
Discuss with a parent or teacher how a number line can help you visualize and plot decimal numbers.
In the Got It? section, you will practice locating decimal numbers on a number line as you play interactive games.