Lesson: Divide Decimals by Decimals
Lesson Objective
Lesson Plan
Teacher: Subject: 
Kurt Sarsfield 5th Grade Math Problem Solving 
Date: March 11, 2010 

Lesson 
Divide Decimals by Decimals to the Thousandths 

SWBAT divide decimals by decimals. 

Vocabulary: 
For review: quotient, divisor, dividend 

Agenda Power Up Brain Bucket Synapse Stretch Notes with Picture It CW—What’s Your Level Exit Ticket and Check 
Introduction to Lesson/Hook
Synapse stretch. Independent in Harvard and McGill. Guided in Augsburg and Michigan.


Picture It What is 0.6 divided into groups of 0.2? 
Read the question on the Picture It. How would I write this word sentence as a number sentence? Let’s think about what this means. What amount is the total I am dividing up? (Rephrase if necessary…What amount am I starting with?) How much will be in each group? So I am putting 0.6 into groups of 0.2. How much is going to be in each group? In my visual, how would I shade 0.6? Now, I am going to make groups using circles. What do I need to circle to make groups of 0.2? (two pieces) If I continue to circle groups of two tenths, how many groups will I have? Did you notice anything about this problem? (too openended for lower classes) I noticed something. What is the quotient of 6 divided by 2? 

Example 1
5.25 ÷ 0.5

First, set up your division problem in the house. This is different than what you did in Ms. Falbo’s class because the divisor has a decimal point. To begin the problem, move the decimal point over one place in the dividend and the divisor. Now, start by bringing up your decimal point to the quotient. Now, I am ready to divide. How many groups of 5 can I make with 5? Write a 1 above the 5. Multiply, subtract and which digit do I bring down? Continue questioning through division.


Example 2
0.468 ÷ 0.4

When I have a decimal in my divisor, what can I do so that there is no longer a decimal in my divisor? After I move the decimal but before I divide, what do I need to write in my quotient? Question through division steps. 

Closure:
Check the exit ticket. Students will check super hero if the question was right, sidekick if they got the correct digits but made an error with the decimal, and apprentice if they did not get the correct answer on this question.

Lesson Resources
5.20 Divide decimals by decimals to the thousandths 5Math ProbSolv Sarsfield 2010.03.11 BL.doc 
1,387

Comments