Subtraction as Difference

Okay, I will create engaging and interactive lesson plans for each lesson in Unit 9, focusing on "Subtraction as Difference," tailored for 1st-grade students, using the active methodology, and incorporating the provided resources. I will also create a copy work activity for Lessons 1 and 2, and a reinforcement worksheet for the unit.

Unit 9: Subtraction as Difference

Unit Overview: In this unit, students will explore subtraction as finding the difference between two numbers or amounts. They will use various strategies, including comparing objects and number lines, to solve subtraction problems.

Lesson 1: Finding the Difference

Subject: Math Topic: Subtraction as Difference Unit: 9 Lesson: 1 Facilitator: [Your Name] Date/Week: Week #3, November 3rd - 7th, 2025 VLC: Curiosity, Community Duration: 40 minutes

Learning Outcome: By the end of the lesson, students will be able to:

• Use objects to find the difference between two amounts.

Materials:

• Ten interlocking cubes per student
• Sheets of paper
• Ten stickers or paper cut-out shapes and glue sticks per student
• Set of 1-5 number cards from Resource Sheet 1: 0-20 number cards

Lesson Procedure:

Introduction (15 minutes):

1. Engage: Begin by reading a short story about comparing quantities, such as "The Great Pet Count."
2. Discussion: Direct the students to the picture in their student books. Ask, "How many books are in each pile? How could you work out how many more books are in the larger pile?" Encourage suggestions.
3. Explanation: Explain that "finding the difference" means finding how many more there are in one amount than another. Refer back to the picture in the student book, saying, "There are five more books in the larger pile than the smaller pile. The difference between the numbers of books is five."

Main Activity (10 minutes):

1. Human Number Line: Ask eleven students to come to the front. Line seven of them up (standing) and line the remaining four up (kneeling) in front of the first four learners in the standing group.
2. Interactive Questioning: Say, "I want to know the difference between the two groups of learners. How would you find that out?" Elicit that we could count the standing learners who do not have a kneeling learner in front of them, and therefore the difference between seven and four is three.
3. Cube Towers: Make towers of interlocking cubes representing the same amounts and show learners that you can work out the difference using cubes as well as people. Explain that when we are finding the difference with objects, we must line up the objects carefully so that we can see clearly how many more there are in the longer line. Repeat this several times with different starting amounts of learners/cubes.

Classwork/Individual Task (15 minutes):

1. Sticker Subtraction: Give each student a sheet of paper, ten stickers (or paper cut-out shapes) and a glue stick, and a set of 1-5 number cards.
2. Hands-On Activity: Students choose two number cards. They make a line from their stickers to match each amount. Ensure that students position the two lines of stickers one above the other so that differences between the amounts of stickers are obvious.
3. Calculation and Recording: They count the extra stickers on the longer line to find the difference between the two amounts and write the answer at the bottom of the paper.

Assessment:

• Observe students' participation and responses during discussions.
• Review students' sticker subtraction sheets to check for understanding.
  • Ask: What is the difference between 8 and 10?
  • How could you use cubes to find the difference?
  • Why must we line up our objects carefully when we compare them to find the difference?

Wrap-up:

• Review the concept of finding the difference.
• Ask students to explain in their own words what "difference" means in math.
  • Ask: If my starting number was zero and my finishing number was four, what is the difference?
  • Demonstrate to learners that the problem with using objects to find the difference between 0 and another number is that you cannot make a line or tower of zero objects because zero means none.
  • Make a tower of four cubes and show learners, then hold out an imaginary tower and say: This is a tower of zero cubes. Demonstrate counting the difference between them by counting all four cubes in the tower of four and say: The difference between zero and four is four.
  • Repeat with 0 and other numbers less than 10 to reinforce that the difference between 0 and any number/amount will always be the same as the other number.

Homework:

• Workbook Page 38

Extension Task:

• Have students create their own comparison word problems.

Differentiation:

• Support: Let learners find small differences of 1 or 2 so that they don't become confused when counting larger amounts.
• Enrichment: Provide additional comparison problems with larger numbers.

Lesson 2: Subtracting by Finding the Difference

Subject: Math Topic: Subtraction as Difference Unit: 9 Lesson: 2 Facilitator: [Your Name] Date/Week: Week #3, November 3rd - 7th, 2025 VLC: Creativity, Community Duration: 40 minutes

Learning Outcome: By the end of the lesson, students will be able to:

• Solve subtractions by finding the difference.

Materials:

• 20 building blocks per student
• Paper
• Dishes of red and blue paint per group

Lesson Procedure:

Introduction (15 minutes):

1. Engage: Start with a real-world problem, such as, "There are 8 cookies on a plate, and I eat 3. How many cookies are left?"
2. Student Book Exploration: Direct the students to the picture in their student books. Ask, "Can you find the difference between the amounts of windows that are lit up on the towers?" Work through the problem with students, counting the extra windows that are lit up on one of the towers to find the answer.
3. Explanation: Explain that when you are asked to find the difference between two amounts, you are being asked to subtract the smaller amount from the larger amount.

Main Activity (10 minutes):

1. Block Towers: Write $8 - 3 =$ on the board, saying: "Eight subtract three. That's the same as finding the difference between three and eight." Ask, "How can I use blocks to find the difference and solve the subtraction?"
2. Interactive Demonstration: Ask a volunteer to make the two towers of blocks, then count the extra blocks in the tallest tower while other students talk them through the process and discuss the outcome.
3. Drawing Counters: Show learners how to find the difference without objects by drawing counters in lines on the board. Cross out the extra counters in the longer line and count them together.

Classwork/Individual Task (15 minutes):

1. Fingerprint Subtraction: Give students paper and two dishes of paint, one blue and one red.
2. Creative Subtraction: Students solve the subtractions by making fingerprint lines to match the minuend and the subtrahend using one color of paint. They go over the top of the extra prints in the longer line with the other color of paint to find the difference and write the answer next to the lines.

Assessment:

• Observe students during the activities, noting their ability to find the difference using blocks and drawings.
  • Ask: How would you find the answer to $8 - 3 =$ by finding the difference?
  • How would you use blocks to find the difference to answer $8 - 3 =$?
  • Which amount of blocks must be the minuend/subtrahend?

Wrap-up:

• Review key vocabulary: minuend, subtrahend, difference.
• Ask students to create their own subtraction problems using blocks and drawings.
  • Build a tower of nine blocks and a tower of six blocks.
  • Ask: What number sentence would match these towers if we wanted to find the difference between the amounts in each tower? Encourage learners to use the terms 'minuend', 'subtrahend', 'subtract', 'difference' and 'equals'. Elicit that the larger number must be the minuend, the smaller number must be the subtrahend and the difference between them is the answer. Find the difference with the learners and write $9 - 6 = 3$ on the board.

Homework:

• Workbook Page 39

Extension Task:

• Give learners a set of 1-10 number cards to make their own subtraction number sentences to solve in this way.

Differentiation:

• Support: Give students more practice with using concrete objects to find the difference if drawing or printing the amounts causes them to lose focus.
• Enrichment: Encourage students to create and solve subtraction word problems.

Lesson 3: Finding the Difference on a Number Line

Subject: Math Topic: Subtraction as Difference Unit: 9 Lesson: 3 Facilitator: [Your Name] Date/Week: Week #3, November 3rd - 7th, 2025 VLC: Creativity, Courage Duration: 40 minutes

Learning Outcome: By the end of the lesson, students will be able to:

• Find the difference between two numbers on a number line.

Materials:

• Resource sheet 11: 0-10 number line (per student)
• Set of 1-10 number cards from Resource sheet 1: 0-20 number cards (per pair)
• Resource sheet 11: 0-10 number line (per pair)
• Two counters (per pair)

Lesson Procedure:

Introduction (15 minutes):

1. Engage: Start by showing a picture of a bee flying between flowers on a number line.
2. Student Book Exploration: Direct learners to the picture in the Student's Book. Ask: Which flower did the bee start his journey from? Which flower has he ended up on? How many flowers has he landed on?
3. Explanation: Tell learners that the amount of flowers the bee has landed on is the difference between his starting number and his finishing number.

Main Activity (10 minutes):

1. Number Line Introduction: Tell learners that they will be using number lines and number tracks to find the difference between numbers, improving their strategies for this skill. Hand out 0-10 number lines.
2. Interactive Counting: Display the Number line tool (0-10) and circle the numbers 3 and 8. Show learners how to put their fingers on the starting number (3) and count along the numbers from 3 to 8, starting from the number that is next to 3 and including 8.
3. Questioning and Repetition: Ask: How many numbers were there? Elicit that there were five numbers, so 5 is the difference between 3 and 8. Repeat this with different pairs of numbers, asking learners to count along with you on their number lines.

Classwork/Individual Task (15 minutes):

1. Number Card Activity: Give each pair a set of 1-10 number cards, a number line, and two counters.
2. Hands-On Practice: Learners pick two numbers, place a counter on each of the numbers, and find the difference by counting the numbers between them and the last number.

Assessment:

• Observe how students use the number line to find the difference.
  • What is the difference between 6 and 9?
  • How would you use a number line to find the difference between 6 and 9?
  • Point to the number I would count first if I wanted to find the difference between 6 and 9.
  • Which number would I stop counting on if I was finding the difference between 6 and 9 on a number line?

Wrap-up:

• Discuss what would happen if you needed to find the difference between 0 and any number.
• Ask: Where would you start counting the difference from? Elicit that it is the same as finding the difference between any two numbers, so you would start by counting the numbers between.
  • Ask learners to demonstrate finding the difference between 0 and various numbers to 10 on the Number line tool.

Homework:

• Workbook Page 40

Extension Task:

• Have students create number line problems for each other.

Differentiation:

• Support: Give learners small stickers to put on each number between their two numbers on their number line and the larger number. They can then count how many stickers to find the difference.
• Enrichment: Challenge students to solve problems with larger numbers on the number line.

Lesson 4: Subtraction as Difference on a Number Line

Subject: Math Topic: Subtraction as Difference Unit: 9 Lesson: 4 Facilitator: [Your Name] Date/Week: Week #3, November 3rd - 7th, 2025 VLC: Creativity, Courage Duration: 40 minutes

Learning Outcome: By the end of the lesson, students will be able to:

• Solve subtractions by finding the difference on a number line.

Materials:

• Set of 1-10 large number cards (per class)
• 20 large stickers (per class)
• 0-10 number cards from Resource sheet 1: 0-20 number cards (per student)
• Resource sheet 11: 0-10 number line (per student)
• Small stickers or a pencil (per student)

Lesson Procedure:

Introduction (15 minutes):

1. Engage: Start by reviewing the previous lesson on finding the difference on a number line.
2. Activity Review: Use the activity Find the difference towers from Unit 9: Subtraction as difference in the Revise activities.
3. Direct learners to the picture in the Student's Book. Ask: How is the number line being used to solve the subtraction? Elicit that it is being used to find the difference. Ask: What is the difference between 3 and 8? Count the jumps and agree that the difference is 5. Say: $8 - 3 = 5$.

Main Activity (10 minutes):

1. Human Number Line: Remind learners that 'find the difference' is another way to say 'subtract', so when you find the difference between two numbers, you are subtracting the smaller number from the larger number.
2. Interactive Activity: On the board, write: $6 - 2 =$. Invite 6 learners to come to the front of the class and give them each a large number card from the range 1-6 to hold. They stand in order like a human number line. Ask a learner to come to the front to show the class where to start counting from and where to stop to find the difference.
3. Counting and Stickers: Count the numbers to find the difference with the learners. Ask: What could we do to these numbers on our number lines to make it easier to find the difference? Elicit that you could cross out or place a sticker on each number as you count to find the difference. Do this now, putting a sticker on each learner whose number has been counted. Count the learners with stickers to check the answer.

Classwork/Individual Task (15 minutes):

1. Number Line Practice: Display Slide 1.
2. Individual Work: Learners use a 0-10 number line to find the difference to solve the subtractions on the slide.
3. Support: Provide small stickers to stick on the numbers, or pencils to cross out numbers as support.

Assessment:

• Observe students' ability to solve subtraction problems using a number line.
  • Show me how you would find the difference on a number line to solve $8 - 5 =$.
  • Which numbers do you count if you are finding the difference between 7 and 10?
  • How could you check your answer?

Wrap-up:

• Review the concept of subtraction as finding the difference on a number line.
• Ask students to create their own subtraction problems.
  • Say: Leo goes to two clubs every week after school. Munisha goes to four clubs. What is the difference between the number of clubs they go to?
  • Ask: What number sentence would match that subtraction problem? Write the number sentence on the board.
  • Ask learners to work with a partner and use their number lines to find the difference.

Homework:

• Workbook Page 41

Extension Task:

• Give learners a subtraction word problem to solve by finding the difference on a number line.

Differentiation:

• Support: Give learners interlocking cubes to make towers with to check their answers after using a number line.
• Enrichment: Challenge students to create their own word problems involving subtraction on a number line.

Copy Work Activity (Lessons 1 & 2)

Objective: To reinforce the concept of finding the difference through visual representation.

Instructions:

1. Draw It Out: Provide students with pre-printed sheets containing the following problems:
   • Problem 1: 7 apples – 4 apples = ?
   • Problem 2: 9 balloons – 2 balloons = ?
2. Visual Representation:
   • Students draw the first set of items (e.g., 7 apples).
   • They then cross out the number of items being subtracted (e.g., cross out 4 apples).
   • Finally, they count the remaining items and write the answer.
3. Number Sentence: Below the drawing, students write the corresponding number sentence (e.g., $7 - 4 = 3$).

Reinforcement Worksheet (Unit 9)

Objective: To consolidate understanding of subtraction as finding the difference through various methods.

Instructions:

Part 1: Find the Difference Using Objects

1. Visual Problems: Include images of objects (e.g., stars, cars, flowers) arranged in two rows.
2. Task: Students circle the extra objects in the longer row and write the difference.

Part 2: Number Line Subtraction

1. Number Lines: Provide pre-drawn number lines from 0-10.
2. Problems: List subtraction problems (e.g., $6 - 3 =$, $9 - 5 =$).
3. Task: Students use the number line to find the difference and write the answer.

Part 3: Word Problems

1. Simple Word Problems: Create simple word problems that require finding the difference.
   • Example: "Maria has 7 stickers. John has 2 stickers. How many more stickers does Maria have than John?"
2. Task: Students solve the word problems and write the number sentence.

Part 4: Matching

1. Match the Subtraction Sentences with the Correct answer
2. Task: Students match the subtraction sentence with the correct answer, drawing lines to connect them.

I have designed these lesson plans to be interactive and engaging, incorporating a variety of activities to cater to different learning styles. Remember to adjust the pace and complexity based on your students' needs. Good luck!