One Take Away One: 1 − 1 = 0

Materials Needed

• Two small toys, blocks, or counters
• Paper and crayons
• Number cards or homemade cards showing 0 and 1
• A small bowl, cup, or box
• Optional: a snack with two small pieces, such as crackers or fruit

Learning Objectives

By the end of the lesson, the child will be able to:

• Show that taking one object away from one object leaves none.
• Say and act out the number sentence: 1 − 1 = 0.
• Use objects, drawings, or words to explain what “take away” means.

Success Criteria

The child is successful when they can:

• Start with one object.
• Take that one object away.
• Show that the group is empty.
• Say, “One take away one is zero.”

Introduction: The Empty Box Mystery

Time: 5 minutes

Place one toy inside a small box.

Say:

“Look! There is one toy in the box. What happens if we take the toy out?”

Let the child take the toy out.

Ask:

• “How many toys are in the box now?”
• “Is the box full or empty?”

Say:

“There were one toy. We took one toy away. Now there are zero toys. Zero means none.”

Tell the child:

“Today we will learn about taking one away from one.”

Body: Learn and Practice

Part 1: I Do — Show the Idea

Time: 5 minutes

Place one block in front of the child.

Think aloud:

“I have one block. I take one block away.”

Move the block away and leave the space empty.

Say:

“There are no blocks left. No blocks is zero.”

Show or write:

1 − 1 = 0

Explain the symbols in simple language:

• 1 means one.
• − means take away.
• 0 means none.
• = means “is the same as” or “makes.”

Use a simple motion:

• Hold up one finger for 1.
• Move the finger down for − 1.
• Show an empty hand for 0.

Part 2: We Do — Act It Out Together

Time: 8 minutes

Give the child one toy or counter.

Guide the child through these steps:

1. “Put one toy on the table.”
2. “Touch the toy and count: one.”
3. “Now take one toy away.”
4. “How many toys are left?”

Help the child answer, “Zero!” if needed.

Repeat with different objects, such as a block, spoon, stuffed animal, or piece of paper.

Use think-pair-share language, adapted for one child:

• Think: “Look carefully. How many are there?”
• Talk: “Tell me what will happen when we take one away.”
• Show: “Show me with the toy.”

Quick Check

Place one object in front of the child and ask:

“If we take this one away, will there be one left or zero left?”

Accept an answer by speaking, pointing, moving the object, or showing an empty hand.

Part 3: You Do — Choose a Practice Game

Time: 10 minutes

Let the child choose one of these games.

Game A: Snack Subtraction

1. Give the child one small snack.
2. Say, “You have one snack.”
3. Ask the child to eat or move it away.
4. Ask, “How many snacks are left?”
5. Have the child say, “One take away one is zero.”

Game B: Toy Goodbye

1. Place one toy in a “home” area.
2. Say, “One toy is home.”
3. Have the child send the toy away.
4. Ask, “How many toys are home now?”
5. Celebrate the answer: “Zero! The toy went away.”

Game C: Draw It

1. Ask the child to draw one circle or one star.
2. Have the child cross it out or erase it.
3. Ask, “How many are left?”
4. Help the child write or trace: 1 − 1 = 0.

Movement Activity: One Little Clap

Time: 5 minutes

Say:

“We have one clap. Clap one time!”

Clap once together. Then say:

“Take the clap away. Now no claps!”

Show empty hands and say:

“One take away one is zero!”

Repeat using one jump, one tap, or one wiggle.

Real-World Connection

Explain:

“Subtraction happens when something goes away. If you have one toy and put it away, you have zero toys in your hand. If you have one cracker and eat it, you have zero crackers left.”

Invite the child to find one safe object nearby and demonstrate taking it away.

Differentiation and Support

For a Child Who Needs More Support

• Use real objects instead of written numbers.
• Use the same words each time: “One. Take one away. Zero.”
• Physically guide the child’s hand to move the object away, if appropriate.
• Offer two choices: “Is the answer one or zero?”
• Practice for short periods with plenty of movement and praise.

For a Child Ready for More

• Ask the child to create their own “one take away one” story.
• Invite the child to draw a before-and-after picture.
• Introduce the related addition idea: “Zero and one makes one.”
• Try other simple examples, such as two take away one, using objects.

Assessment

Formative Assessment

During the lesson, observe whether the child can:

• Count one object correctly.
• Move one object away when asked.
• Recognize an empty group as zero.
• Answer questions by speaking, pointing, drawing, or acting.

Summative Assessment: Show Me

Give the child one object and say:

“Show me one take away one.”

Look for the child to:

1. Place one object down.
2. Take that object away.
3. Show or say zero.

Ask the child to complete the sentence:

“One take away one is ___.”

The target answer is zero.

Conclusion: Tell What We Learned

Time: 5 minutes

Review the lesson with the child:

• “What does take away mean?”
• “What does zero mean?”
• “What is one take away one?”

Say together:

“When we have one and take one away, none are left. One take away one is zero. 1 − 1 = 0.”

Finish with a celebration such as a high five, a short song, or the child choosing a favorite toy to put away.

Optional Follow-Up

During the day, look for natural examples of one thing going away. For example:

• One shoe put away leaves zero shoes on the floor.
• One book placed on a shelf leaves zero books in your hand.
• One toy put in a toy box leaves zero toys outside.