Place value- recognizing and writing common decimal numbers
8,000 schools use Gynzy
92,000 teachers use Gynzy
1,600,000 students use Gynzy
Students learn to write and say common decimal numbers (0.5, 0.25, 0.75, tenths, and hundredths).
It is important that students know how to say decimal numbers, so they better understand how decimal numbers fit together and their link to fractions. An example would be when they hear a sports commentator say "Their scores are only four hundredths apart" when talking about the first and second place athletes.
Refresh the situations in which you would use a decimal number, namely if you can divide the object into smaller parts. Discuss the meaning of the decimal number, decimal point and decimal places. How many decimal places do the numbers have?
Discuss the terms half, quarter, and three quarters using the images on the interactive whiteboard. Using the number line, show how often they fit into one whole.
The decimal number of 0.5 is said as one half. It is half of 1, because it fits into 1 two times.
The decimal number of 0.25 is said as one quarter. It is a quarter of 1 because it fits into 1 four times.
The decimal number of 0.75 is said as three quarters. It is a group of three 0.25s. It is almost one whole 1.
The decimal number of 0.1 is said as a tenth. A tenth fits into 1 ten times.
The decimal number of 0.01 is said as one hundredth. A hundredth fits into 1 one hundred times.
Check that students are able to say the decimal numbers by asking the following questions:
- How do you write "a quarter" in decimal numbers?
- How do you write "three quarters" in decimal numbers?
- How do you say 0.06?
- How do you say 0.08?
- How do you say 0.09?
- How do you say 0.22? (This is a challenge question for advanced students, but is not present in the exercises.)
Students practice with three listening exercises. They hear a number and must first choose, then write the correct decimal number.
Ask students when it is useful to know how to say decimal numbers. An example would be when someone is sick and you need to know their exact temperature of 103.2 degrees. Or if you are timing someone on a stopwatch and there are 6 minutes and 14 hundredths. Finish with an exercise in which students must draw a line between the written decimal number and how to say that decimal number.
Repeat often that these decimal numbers can be said in multiple ways. It must be clear to students that 0.25 is exactly the same as a quarter and 0.01 is the same as a hundredth.
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.