Place value- introduction to decimal points

General

Students learn what a decimal number is and what it is used for.

Common core standard(s)

-4.NF.C.5
-4.NF.C.6

Relevance

Decimal numbers can be seen all around us. Examples are when you buy something for $2.25 or weigh 61.9 pounds.

Introduction

Look at the coins and count the total number of cents they represent.

Development

Explain that decimal numbers are made up of a whole number and a decimal point, followed by more numbers that represent parts of a whole number. The interactive whiteboard shows images of decimal numbers. Discuss with students what the link between decimal numbers and the images are. Explain to students when you can use a decimal number, namely if the object can be split into multiple parts. Tell students that you cannot use a decimal number on whole objects like people or animals.

To check that students understand what decimal numbers are and where they can find them, you can ask the following questions:
- Where can you find decimal numbers?
- Why do you use a decimal number?
- What do the numbers after the decimal point mean?

Guided practice

Students practice recognizing when to use a decimal number and matching decimal numbers to their situations/images.

Closing

Play a game in which students must indicate if a number should be a decimal number or not. The interactive whiteboard has images with text that can be read aloud. Students stand if they believe it is a decimal number, and sit down if the number cannot be a decimal number.

Teaching tips

You can explain the different meanings of numbers in situations if a student finds them overwhelming. Giving the one concrete example of money is a clear base for students who have difficulty understanding decimal numbers, or have trouble finding them around them.

Instruction materials

You can include objects that use decimal numbers: stopwatch, scale, coins, etc.

About Gynzy

Gynzy is an online teaching platform for interactive whiteboards and displays in schools.

With a focus on elementary education, Gynzy’s Whiteboard, digital tools, and activities make it easy for teachers to save time building lessons, increase student engagement, and make classroom management more efficient.