Lesson Plan

# GoMath 5.2 Record Related Facts

Record Related Facts
Sheila G.
Classroom teacher
Bryan Elementary School
Lexington, United States
My Subjects English Language Arts, Math, Science, Social Studies, English-Language Learning
Objectives

Students will be able to...show their understanding of how related facts help you find unknown numbers.

Students will be able to...record related facts within 20.

Nebraska Math Standard: MA 1.2.1.b Use the relationship of addition and subtraction to solve subtraction problems (e.g., find 12 – 9 = ___, using the addition fact 9 + 3 = 12).

Subjects
Math

#### 1 Engage

Using teacher iPad, apple tv, and projector, project the interactive student edition lesson 5.2.  Pass the iPad having individuals work collaboratively to work through the interactive edition.

Guide children in a discussion about related facts by focusing their attention on the groups of kites.

Describe the kites you see. 3 green kites and 2 red kites

What addition fact describes the kites? 3 + 2

In describing the kites what does the number sentence 3 + 2 = 5 mean? 3 green kites plus 2 red kites equals 5 kites in all

What does Avery want to do? Possible answer: find other number sentences that tell about the kites

#### 2 Explore

Using Avermedia and projector, project the student workbook page 261.  Students will each have their individual workbooks.

Read the following problem aloud. Then use the questions below to guide children.

Colin has 7 crackers. He gets 1 more cracker. How many crackers does Colin have now? 8

• What do you need to find? the number of crackers Colin has now

Project Go Math iTool to show the number of crackers Colin has.

• How can you use cubes to find how many crackers Colin has? Possible answer: I can make a red cube train to show 7 crackers and 1 blue cube to show 1 cracker. Then I can count all the cubes.

Colin has 8 crackers. He gives one to Jacob. How many crackers does Colin have now? 7

How is this problem like the first problem? How is it different? Possible answers: Colin gets one cracker in the first problem. Colin gives one cracker away in the second problem.

In the first problem you added. What do you need to do in this problem? Possible answer: I need to subtract one cracker from 8.

How can you use your cubes from the first problem to find how many crackers Colin has now? Possible answer: I can take one cube away from the 8-cube train.

#### 3 Explain/Guided Practice

Work through the model and the pictures on workbook page 262 with students.

•  How does knowing one addition fact help you find all the related facts? I can change the order of the addends in one addition fact to get the other addition fact. I know the parts and the whole from the addition facts, so I can write two different subtraction facts.

•  How do the addition cube trains look the same? How do they look different? Both show 4 red cubes and 5 blue cubes; the second cube train shows the same addends in a different order.

•  How do the subtraction trains look the same? How do they look different? Both show 4 red cubes and 5 blue cubes; the second cube train shows the same numbers in a different order. The cubes on the right side of the train (red or blue) are broken off and crossed out.

•  Why are the addition and subtraction sentences using 4, 5, and 9 called related facts? Possible answer: The addition and subtraction sentences all have the same parts and whole.

#### 4 Elaborate/Independent Practice

View the Math on the Spot video for Go Math lesson 5.2.

Have students complete workbook pages 263-264.  Provide support and correction as needed.

#### 5 IXL Practice

IXL - Math and English
Free to try, Paid

As students successfully complete their workbook pages, have them get an iPad from the mobile lab.  Students should use the IXL app to practice fact families (F.3)