# Lesson 5

Subtract with Objects

## Warm-up: How Many Do You See: Subtraction (10 minutes)

### Narrative

The purpose of this How Many Do You See is to allow students to subitize or use grouping strategies to describe the images they see (MP7). They may additionally make use of structure (MP7) because in successive images the arrangement of dots remains the same, but some dots are removed.

### Launch

• Groups of 2
• “How many dots do you see and how do you see them?”
• Flash image.
• 30 seconds: quiet think time

### Activity

• Display image.
• 1 minute: partner discussion
• Record responses.
• Repeat for each image.

### Student Facing

How many do you see?
How do you see them?

### Student Response

For access, consult one of our IM Certified Partners.

### Activity Synthesis

• Display the image with 6 dots and the image with 4 dots in the same configuration.
• “What changed from this group of dots to the next?” (Some of the dots were taken away.)
• “We have been working on adding objects. Today we are going to learn about how to subtract, or take away, objects.”

## Activity 1: Subtract Counters (10 minutes)

### Narrative

The purpose of this activity is for students to represent subtraction with objects. Students connect the action of subtraction with the language “take away.”

MLR8 Discussion Supports. Use multimodal examples. Count aloud and use exaggerated gestures to demonstrate the meaning of “take away.”

### Required Materials

Materials to Gather

### Launch

• Groups of 2
• Give each student at least 10 counters.
• “Count out 4 counters.”
• 30 seconds: independent work time
• “You have 4 counters. Now take away 2 of the counters.”
• 30 seconds: independent work time
• Write “4 take away 2.”
• “How many counters do you have now?” (2)
• 30 seconds: quiet think time
• Select a student to share what they did with the counters and how many counters they have left.
• “I’m going to write a 2 on the line. Now my sentence says ‘There are 2 counters left.’”

### Activity

• Read each prompt to students. Pause between each line to give students time to count out and take away the counters and record the difference.
• “Which counters did you take away?”
• “Which counters are left?”

### Student Facing

1. Count out 8 counters.
Take away 3 counters.

There are

counters left.

2. Count out 10 counters.
Take away 6 counters.

There are

counters left.

3. Count out 7 counters.
Take away 1 counter.

There are

counters left.

4. Count out 9 counters.
Take away 3 counters.

There are

counters left.

### Student Response

For access, consult one of our IM Certified Partners.

### Activity Synthesis

• Display 6 counters.
• “I have 6 counters. I am going to take away 4 counters.”
• Take away 4 counters.
• “6 take away 4 is 2.”

## Activity 2: Introduce 5-Frames, Subtract (10 minutes)

### Narrative

The purpose of this activity is for students to learn stage 2 of the 5-frames center. Students represent subtraction with objects. Students begin with 5 counters on a 5-frame, take some counters away, and figure out how many counters are left.

The recording sheet is printed in the student book for this activity. There is a blackline master available for students to use during centers in future activities and lessons.

Representation: Access for Perception. Synthesis: Students may benefit from demonstrating the concept of “5 take away 2.” Use 5-frames and counters to demonstrate the action of this so that students see how “5 take away 2” produces the final 3 counters in the 5-frame.
Supports accessibility for: Conceptual Processing, Visual-Spatial Processing

### Required Materials

Materials to Gather

Materials to Copy

• Number Mat 1–5

### Required Preparation

• Each group of 2 needs 1 connecting cube.

### Launch

• Give each group 1 connecting cube, 10 counters, and a number mat.
• “We are going to learn a new way to do the 5-frames center. It is called 5-Frames, Subtract.”
• Display a 5-frame filled with 5 counters.
• “For each round in this game, you will begin by filling the 5-frame at the top of the recording sheet with counters. Then you will roll the cube onto the number mat to see how many counters you will take away. One partner rolls the cube and the other takes the counters away.”
• Demonstrate filling in the 5-frame with counters.
• Invite a student to be your partner and roll the cube onto the number mat.
• “My partner rolled a 3 so I am going to take away 3 counters.”
• Demonstrate taking away 3 counters and placing them to the side.
• “After you take away the counters, figure out how many counters are left and write the number on the recording sheet.”
• Write the number 2 on the recording sheet.
• “Now you will play with your partner. Take turns rolling the cube and taking away the counters.”

### Activity

• 5 minutes: partner work time

### Student Response

For access, consult one of our IM Certified Partners.

### Activity Synthesis

• Show a 5-frame with 3 counters.
• “How many counters did we take away? How do you know?”
• Write and invite students to chorally repeat “5 take away 2.”
• “How many counters do we have left?”
• Write “There are 3 counters left.”

## Activity 3: Centers: Choice Time (25 minutes)

### Narrative

The purpose of this activity is for students to choose from activities that offer practice adding and subtracting with objects and images, writing numbers, and describing and building with shapes.

Students choose from any stage of previously introduced centers.

• 5-Frames
• Math Libs
• Match Mine

### Required Materials

Materials to Gather

### Required Preparation

• Gather materials from:
• 5-Frames, Stages 1 and 2
• Roll and Add, Stage 1
• Math Libs, Stage 1
• Match Mine, Stage 1

### Launch

• “Today we are going to choose from centers we have already learned. You can also continue playing 5-frames.”
• Display the center choices in the student book.
• “Think about what you would like to do first.”
• 30 seconds: quiet think time

### Activity

• Invite students to work at the center of their choice.
• 10 minutes: center work time
• “Choose what you would like to do next.”
• 10 minutes: center work time

Choose a center.

5-frames

Math Libs

Match Mine

### Activity Synthesis

• Display a full 5-frame.
• “Han is playing 5-Frames Subtract. He rolled the cube and landed on 1. He says he has 6 counters now. What do you think?”

## Lesson Synthesis

### Lesson Synthesis

“Today we took away, or subtracted, with counters. How is subtracting different than adding?” (When you subtract, you are taking some things away. When you add, you are getting more things or putting things together. When you subtract, you have fewer things. When you add, you get more things.)

## Cool-down: Unit 4, Section A Checkpoint (0 minutes)

### Cool-Down

For access, consult one of our IM Certified Partners.

## Student Section Summary

### Student Facing

In this section, we counted two groups of things to figure out how many there are altogether.

3 yellow counters and 4 red counters is 7 counters.

3 and 4 is 7.

We added more things and found out how many there were altogether.

There were 5 counters on the 5-frame and we added 4 more counters.

5 and 4 is 9.

We subtracted, or took away, some things and figured out how many were left.

There were 5 counters on the 5-frame and we took away 2 of them.

5 take away 2 is 3.