The purpose of this True or False is for students to demonstrate strategies and understandings they have for comparing decimals. These understandings will be valuable when students order decimals later in this lesson. As students discuss and justify their decisions, they share a mathematical claim and the thinking behind it (MP3).
Launch
Display one statement.
“Give me a signal when you know whether the statement is true and can explain how you know.”
1 minute: quiet think time
Teacher Instructions
Share and record answers and strategy.
Repeat with each statement.
Student Task
Decide if each statement is true or false. Be prepared to explain your reasoning.
0.909>0.91
4.1<4.100
0.99<0.999
Sample Response
False: 0.910 is larger because it has a one in the tenths place.
False: 4.1 is equal to 4.100.
True: 0.99 is equal to 0.990 which is less than 0.999.
Activity Synthesis (Teacher Notes)
“Is the statement 0.909>0.91 true or false? How do you know?” (False, because 0.909 has 9 tenths and 9 thousandths and 0.91 is 9 tenths and 1 hundredth. 1 hundredth is greater than 9 thousandths.)
Display: 0.909 and 0.910
“How does writing the numbers like this help to compare them?” (I can see that 0.910 has 10 thousandths compared to 9 for 0.909.)
Standards
Addressing
5.NBT.3.b·Compare two decimals to thousandths based on meanings of the digits in each place, using >, =, and < symbols to record the results of comparisons.
5.NBT.A.3.b·Compare two decimals to thousandths based on meanings of the digits in each place, using <span class="math">\(>\)</span>, =, and <span class="math">\(<\)</span> symbols to record the results of comparisons.
20 min
15 min
Knowledge Components
All skills for this lesson
No KCs tagged for this lesson
Order Decimals
10 min
Narrative
The purpose of this True or False is for students to demonstrate strategies and understandings they have for comparing decimals. These understandings will be valuable when students order decimals later in this lesson. As students discuss and justify their decisions, they share a mathematical claim and the thinking behind it (MP3).
Launch
Display one statement.
“Give me a signal when you know whether the statement is true and can explain how you know.”
1 minute: quiet think time
Teacher Instructions
Share and record answers and strategy.
Repeat with each statement.
Student Task
Decide if each statement is true or false. Be prepared to explain your reasoning.
0.909>0.91
4.1<4.100
0.99<0.999
Sample Response
False: 0.910 is larger because it has a one in the tenths place.
False: 4.1 is equal to 4.100.
True: 0.99 is equal to 0.990 which is less than 0.999.
Activity Synthesis (Teacher Notes)
“Is the statement 0.909>0.91 true or false? How do you know?” (False, because 0.909 has 9 tenths and 9 thousandths and 0.91 is 9 tenths and 1 hundredth. 1 hundredth is greater than 9 thousandths.)
Display: 0.909 and 0.910
“How does writing the numbers like this help to compare them?” (I can see that 0.910 has 10 thousandths compared to 9 for 0.909.)
Standards
Addressing
5.NBT.3.b·Compare two decimals to thousandths based on meanings of the digits in each place, using >, =, and < symbols to record the results of comparisons.
5.NBT.A.3.b·Compare two decimals to thousandths based on meanings of the digits in each place, using <span class="math">\(>\)</span>, =, and <span class="math">\(<\)</span> symbols to record the results of comparisons.