Lesson Plan
Commutative Crew: Day 1 Lesson Plan
Students will review asking and answering 'how many more/less' questions (MD.4) and begin to understand and apply the commutative property of addition (OA.3) by recognizing that changing the order of addends does not change the sum.
Understanding the commutative property makes addition more flexible and helps students solve problems more efficiently. Reviewing 'how many more/less' strengthens their data interpretation and subtraction skills.
Audience
1st Grade Students
Time
50 minutes
Approach
Direct instruction, interactive slides, partner work, and hands-on activities.
Materials
Whiteboard or projector, Markers/pens, Counting objects (e.g., blocks, counters), Commutative Crew Day 1 Slide Deck, Commutative Crew Day 1 Script, and Commutative Crew Day 1 Worksheet
Prep
Teacher Preparation
15 minutes
- Review all generated materials: Commutative Crew Day 1 Lesson Plan, Commutative Crew Day 1 Slide Deck, Commutative Crew Day 1 Script, and Commutative Crew Day 1 Worksheet.
- Gather counting objects (blocks, counters, etc.) for small group activity.
- Prepare whiteboard or projector for interactive examples.
Step 1
Warm-up & Spiral Review (MD.4)
5 minutes
Project the spiral review question from the Commutative Crew Day 1 Slide Deck.
- Ask students to identify 'how many more' or 'how many less' based on the displayed data.
- Facilitate a quick class discussion to share answers and strategies.
Step 2
Introduction to Commutative Property (OA.3)
15 minutes
Use the Commutative Crew Day 1 Slide Deck and Commutative Crew Day 1 Script to guide instruction.
- Introduce the term 'commutative property' in a child-friendly way (e.g., 'flip-flop numbers').
- Demonstrate with examples using counting objects (e.g., 2+3 and 3+2).
- Have students practice simple examples with their fingers or quick drawings.
Step 3
Small Group Activity: Commutative Creations
30 minutes
- Divide students into small groups.
- Provide each group with counting objects.
- Instruct groups to create addition problems and then 'flip' the numbers to show the commutative property. For example, if they make 4+1, they then make 1+4.
- Have them record their findings on the Commutative Crew Day 1 Worksheet.
- Circulate to provide support and ask guiding questions.
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Slide Deck
Add It Up: Commutative Crew! Day 1
Today, we're going to become addition detectives and learn about a super cool math trick!
Welcome students and introduce the day's topic. Get them excited about becoming 'Commutative Crew' members!
Warm-up: Fruit Count!
Look at the fruit stand!
Apples ššššš
Bananas ššš
Question: How many more apples are there than bananas?
Display a simple pictograph or bar graph. For example:
Apples: 5
Bananas: 3
Ask the class: "How many more apples are there than bananas?" or "How many less bananas are there than apples?" Allow a few seconds for students to think and then call on a few to share their answers and how they figured it out. This is a quick spiral review to activate their minds on MD.4.
Meet the Commutative Property!
It's a fancy name for a simple idea!
Commutative Property of Addition: When you add numbers, you can change the order of the numbers, and the answer stays the same.
Think of it like 'flipping' the numbers around!
Example: 2 + 3 = 5
What if we flip it? 3 + 2 = ?
It's still 5! The answer doesn't change!
Introduce the commutative property. Use simple language and visuals. Emphasize that the 'order' can change, but the 'total' stays the same. Use the visual of flipping numbers.
Let's See It in Action!
Imagine you have...
šµšµ (2 blue circles)
š“š“š“ (3 red circles)
2 + 3 = ?
Now, let's swap them!
š“š“š“ (3 red circles)
šµšµ (2 blue circles)
3 + 2 = ?
What do you notice about the answer?
Provide concrete examples. Use visuals on the slide or actual manipulatives if available in class. Have students confirm the sum each time.
Your Turn to Explore!
You'll be working in small groups with some counting objects.
Your mission: Create addition problems, then 'flip' the numbers to see if the sum stays the same!
Be ready to share your discoveries!
Introduce the idea of practicing. Explain that they will be working in small groups with objects to explore this idea further. Remind them to think about how the numbers 'flip' but the total stays the same.
Script
Commutative Crew: Day 1 Script
Welcome (0-1 minute)
"Good morning, future math masters! Welcome to our 'Add It Up: Commutative Crew' training! Today, we're going to uncover a super cool secret about addition. Are you ready to become addition detectives?"
Warm-up & Spiral Review (MD.4) (4-5 minutes)
"Let's get our brains warmed up with a quick challenge! Take a look at the screen. We have a fruit stand today! I see some apples and some bananas."
(Display Commutative Crew Day 1 Slide Deck - Slide: Warm-up: Fruit Count!)
"Can you tell me, how many more apples are there than bananas? Raise a quiet hand when you have your answer and how you found it."
(Pause for responses. Call on a few students. Guide them to articulate their thinking, e.g., "I saw 5 apples and 3 bananas, and 5 minus 3 is 2, so there are 2 more apples.")
"Excellent job, detectives! That was a perfect way to review 'how many more' and 'how many less'. It helps us understand our numbers better!"
Introduction to Commutative Property (OA.3) (15 minutes)
"Now, for our big secret of the day! We're going to learn about something called the Commutative Property of Addition. Say that with me: Co-MMU-ta-tive Property!"
(Display Commutative Crew Day 1 Slide Deck - Slide: Meet the Commutative Property!)
"It sounds like a super long, super fancy word, right? But it means something really simple and super helpful. It just means that when you add numbers, you can change the order of the numbers, and the answer, the sum, stays exactly the same!"
"Think of it like 'flipping' the numbers around. Let's try an example together. If I have 2 blue circles and I add 3 red circles, what do I get in total?"
(Wait for '5')
"Exactly! 2 + 3 = 5."
(Display Commutative Crew Day 1 Slide Deck - Slide: Let's See It in Action!)
"Now, what if I start with the 3 red circles and then add the 2 blue circles? What do I get?"
(Wait for '5')
"Wow! 3 + 2 = 5! It's the same answer! We just flipped the numbers around, and the total stayed the same. That's the commutative property in action! The numbers 'commute' or 'travel' to a different spot, but their sum stays solid."
"Let's try another one. Show me 1 finger on one hand and 4 fingers on the other. How many fingers altogether? (5)"
"Now, flip it! Show me 4 fingers on one hand and 1 finger on the other. How many now? (5) See? The order doesn't change the sum!"
Small Group Activity: Commutative Creations (30 minutes)
"Alright, Commutative Crew! It's time for you to become active explorers!"
(Display Commutative Crew Day 1 Slide Deck - Slide: Your Turn to Explore!)
"I'm going to divide you into small groups. Each group will get some counting objects, like blocks or counters. Your mission is to work together to create addition problems, just like we did with the circles and fingers. Then, you'll 'flip' the numbers and show that the sum is still the same!"
"You'll record your work on this Commutative Crew Day 1 Worksheet. Make sure to draw or write down your examples for both ways of adding."
"I'll be walking around to help and see all the amazing commutative creations you come up with. Remember, the goal is to show how changing the order doesn't change the sum!"
(Circulate, observe, and assist students. Ask questions like: "What numbers are you adding?", "What happens when you switch them?", "Does your total change?", "Why do you think this property is useful?")
Wrap-up (Remaining time, if any)
"Fantastic work today, everyone! We explored the Commutative Property and saw how numbers can be added in any order to get the same sum. Keep an eye out for more math secrets tomorrow!"
Worksheet
Commutative Crew: Day 1 Worksheet
Name: _________________________
Date: _________________________
Commutative Creations!
Directions: Use your counting objects (like blocks or counters) to solve these addition problems. First, show the problem one way. Then, show the flipped way. What do you notice about the answer?
Problem 1:
Draw your first addition problem:
____ + ____ = ____
Now, flip the numbers!
____ + ____ = ____
Problem 2:
Draw your first addition problem:
____ + ____ = ____
Now, flip the numbers!
____ + ____ = ____
Problem 3:
Draw your first addition problem:
____ + ____ = ____
Now, flip the numbers!
____ + ____ = ____
Think About It!
What did you notice about the answer (the sum) when you flipped the order of the numbers in your addition problems?
Lesson Plan
Commutative & Associative Crew: Day 2 Lesson Plan
Students will continue to practice asking and answering 'how many more/less' questions (MD.4) and begin to understand the associative property of addition (OA.3) by recognizing that changing the grouping of three or more addends does not change the sum.
Understanding the associative property provides another powerful tool for solving addition problems with multiple numbers, making mental math easier and building a deeper number sense. Continued review of MD.4 reinforces essential comparison skills.
Audience
1st Grade Students
Time
50 minutes
Approach
Review, direct instruction, interactive slides, and small group exploration with manipulatives.
Materials
Whiteboard or projector, Markers/pens, Counting objects (e.g., blocks, counters), Commutative & Associative Crew Day 2 Slide Deck, Commutative & Associative Crew Day 2 Script, and Commutative & Associative Crew Day 2 Worksheet
Prep
Teacher Preparation
15 minutes
- Review all generated materials: Commutative & Associative Crew Day 2 Lesson Plan, Commutative & Associative Crew Day 2 Slide Deck, Commutative & Associative Crew Day 2 Script, and Commutative & Associative Crew Day 2 Worksheet.
- Gather counting objects (blocks, counters, etc.) for small group activity.
- Prepare whiteboard or projector for interactive examples.
Step 1
Warm-up & Spiral Review (MD.4)
5 minutes
Project the spiral review question from the Commutative & Associative Crew Day 2 Slide Deck.
- Present a new data set (e.g., number of blue cars vs. red cars).
- Ask students to determine 'how many more' or 'how many less' and discuss strategies.
Step 2
Introduction to Associative Property (OA.3)
15 minutes
Use the Commutative & Associative Crew Day 2 Slide Deck and Commutative & Associative Crew Day 2 Script to guide instruction.
- Introduce the associative property with three addends.
- Explain that changing the grouping (using parentheses) does not change the sum.
- Demonstrate with simple examples using counting objects (e.g., (1+2)+3 vs. 1+(2+3)).
Step 3
Small Group Activity: Grouping Game
30 minutes
- Divide students into small groups.
- Provide each group with counting objects.
- Instruct groups to set up three groups of objects and explore different ways to add them by grouping two numbers first (e.g., (2+1)+3 and 2+(1+3)).
- Have them record their findings on the Commutative & Associative Crew Day 2 Worksheet.
- Circulate to provide support and ask guiding questions.
Slide Deck
Add It Up: Commutative & Associative Crew! Day 2
Welcome back, addition explorers! Yesterday, we learned about the Commutative Property. Today, we have another amazing math secret to uncover!
Welcome students back and briefly recap the commutative property from Day 1.
Warm-up: Toy Car Count!
Look at the toy cars!
Blue Cars ššššššš
Red Cars šššš
Question: How many more blue cars are there than red cars?
Display a simple pictograph or bar graph for toy cars. For example:
Blue Cars: 7
Red Cars: 4
Ask the class: "How many more blue cars are there than red cars?" or "How many less red cars are there than blue cars?" Allow students to share answers and strategies, reinforcing MD.4.
Quick Commutative Recap!
Yesterday, we learned that with addition, you can FLIP the order of the numbers, and the sum stays the same!
Example: 4 + 2 = 6 AND 2 + 4 = 6
Cool, right?
Quickly review the commutative property. "Remember the Commutative Property? It means you can flip the numbers and the sum stays the same! Like 2+3 is the same as 3+2. Give me a thumbs up if you remember this!"
New Secret: The Associative Property!
Today, we have another amazing property! It's called the Associative Property of Addition.
This one is about GROUPING numbers when you have three or more to add. You can change how you group them, and the sum will still be the same!
We use special symbols called parentheses ( ) to show which numbers we are adding first.
Introduce the Associative Property. Explain that it's about grouping numbers when you have more than two to add. Use parentheses to show the grouping.
Let's Group It Up!
Imagine you have:
ā (1 star)
šš (2 stars)
āØāØāØ (3 stars)
We want to add 1 + 2 + 3.
Option 1: (1 + 2) + 3
First, group 1 + 2. That equals 3.
Then add 3 + 3. That equals 6!
Option 2: 1 + (2 + 3)
First, group 2 + 3. That equals 5.
Then add 1 + 5. That equals 6!
See? The total is the same! We just changed who we added first!
Use concrete examples with visuals. Show (1+2)+3 and then 1+(2+3). Emphasize that the numbers themselves don't move, just the friends they are adding with first.
Your Turn: Grouping Game!
Now it's your turn to play the grouping game!
In your small groups, you'll use counting objects to explore the Associative Property.
Set up three groups of objects, and try adding them in different ways by grouping two numbers first.
Record your discoveries on your worksheet!
Explain the small group activity. Reinforce using manipulatives and recording on their worksheet. Encourage them to see that the total remains consistent regardless of grouping.
Script
Commutative & Associative Crew: Day 2 Script
Welcome & Recap (0-1 minute)
"Welcome back, amazing Addition Crew! Yesterday, we learned about the Commutative Property ā remember how we could flip the numbers and the sum stayed the same? Give me a thumbs up if you remember that!"
"Today, we have another incredible math secret to unlock. It's going to help us add even more numbers together!"
Warm-up & Spiral Review (MD.4) (4-5 minutes)
"Let's warm up our brains with another data detective challenge! Look at the screen. We have a collection of toy cars today."
(Display Commutative & Associative Crew Day 2 Slide Deck - Slide: Warm-up: Toy Car Count!)
"Here are some blue cars and some red cars. Can you tell me, how many more blue cars are there than red cars? Or, how many less red cars are there than blue cars? Think about it, then raise a quiet hand to share."
(Pause for responses. Call on a few students, encouraging them to explain their thinking. "I counted 7 blue cars and 4 red cars. 7 - 4 = 3, so there are 3 more blue cars.")
"Fantastic job, detectives! You're getting so good at comparing numbers!"
Introduction to Associative Property (OA.3) (15 minutes)
"Alright, let's dive into our new secret! Today we're learning about the Associative Property of Addition. Say it with me: Uh-SO-she-a-tive Property!"
(Display Commutative & Associative Crew Day 2 Slide Deck - Slide: New Secret: The Associative Property!)
"This property is super useful when we have three or more numbers we want to add together. It tells us that we can change the GROUPING of the numbers, and the sum will still be the same!"
"We use special symbols called parentheses ( ) to show which numbers we are going to add first. It's like those numbers are holding hands and saying, 'We're going to add each other up before anyone else!'"
(Display Commutative & Associative Crew Day 2 Slide Deck - Slide: Let's Group It Up!)
"Let's look at an example. Imagine we have 1 star, 2 stars, and 3 stars. We want to add 1 + 2 + 3.
"What if we group the 1 and 2 first? We write it like this: (1 + 2) + 3. What is 1 + 2? (3) Great! So now we have 3 + 3, which is...? (6) Wonderful!"
"Now, what if we group the 2 and 3 first? We write it like this: 1 + (2 + 3). What is 2 + 3? (5) Awesome! So now we have 1 + 5, which is...? (6) Amazing!"
"Did the total change? No! It was 6 both times! The numbers didn't move their spots, but we just changed who they added with first, or how they were grouped. That's the Associative Property!"
"Let's try with our fingers. Show me 1 finger on one hand, 2 fingers on another, and 3 on another. How can we group them? Maybe add 1 and 2 first (3), then add 3 (6). Or add 2 and 3 first (5), then add 1 (6). It all comes out the same!"
Small Group Activity: Grouping Game (30 minutes)
"Alright, Commutative & Associative Crew! It's time for our 'Grouping Game'!"
(Display Commutative & Associative Crew Day 2 Slide Deck - Slide: Your Turn: Grouping Game!)
"I'm going to put you back into your small groups. You'll get counting objects again. Your mission today is to set up three different groups of objects. Then, you'll explore adding them in two different ways by changing how you group them with the parentheses."
"You'll record your discoveries on your Commutative & Associative Crew Day 2 Worksheet. Make sure to write out the problem with the parentheses and show the steps."
"I'll be circulating to see your amazing grouping strategies. Remember, the goal is to show how changing the grouping doesn't change the sum!"
(Circulate, observe, and assist students. Ask questions like: "What three numbers are you adding?", "Which two are you grouping first?", "Does your total change when you group them differently?", "How do the parentheses help us know what to do first?")
Wrap-up (Remaining time, if any)
"Wonderful exploration today, everyone! We unlocked the secret of the Associative Property ā how we can group numbers differently and still get the same sum. Keep thinking about how these properties make addition fun and flexible!"
Worksheet
Commutative & Associative Crew: Day 2 Worksheet
Name: _________________________
Date: _________________________
Associative Grouping Game!
Directions: Use your counting objects to solve these addition problems with three numbers. Show two different ways to group the numbers using parentheses ( ) and write the sum. Remember, the numbers stay in the same order, but who you add first changes!
Problem 1:
Let's add: 2 + 1 + 3
Way 1: Group the first two numbers
( ____ + ____ ) + ____ = ____
Show your work with drawings or numbers:
Way 2: Group the last two numbers
____ + ( ____ + ____ ) = ____
Show your work with drawings or numbers:
Problem 2:
Let's add: 4 + 2 + 1
Way 1: Group the first two numbers
( ____ + ____ ) + ____ = ____
Show your work with drawings or numbers:
Way 2: Group the last two numbers
____ + ( ____ + ____ ) = ____
Show your work with drawings or numbers:
Problem 3:
Let's add: 3 + 3 + 2
Way 1: Group the first two numbers
( ____ + ____ ) + ____ = ____
Show your work with drawings or numbers:
Way 2: Group the last two numbers
____ + ( ____ + ____ ) = ____
Show your work with drawings or numbers:
Think About It!
What did you notice about the answer (the sum) when you changed how you grouped the numbers in your addition problems?
Lesson Plan
Commutative & Associative Crew: Day 3 Lesson Plan
Students will continue to practice asking and answering 'how many more/less' questions (MD.4) and apply both the commutative and associative properties of addition (OA.3) to solve problems with three or more addends.
Applying these properties helps students develop mental math strategies, understand number relationships more deeply, and solve more complex addition problems with confidence. Continued practice with MD.4 reinforces data analysis and comparison skills.
Audience
1st Grade Students
Time
50 minutes
Approach
Spiral review, direct instruction, guided practice, partner problem-solving, and a quick exit ticket.
Materials
Whiteboard or projector, Markers/pens, Counting objects (optional, for struggling students), Commutative & Associative Crew Day 3 Slide Deck, Commutative & Associative Crew Day 3 Script, Commutative & Associative Crew Day 3 Worksheet, and Commutative & Associative Crew Day 3 Cool Down
Prep
Teacher Preparation
15 minutes
- Review all generated materials: Commutative & Associative Crew Day 3 Lesson Plan, Commutative & Associative Crew Day 3 Slide Deck, Commutative & Associative Crew Day 3 Script, Commutative & Associative Crew Day 3 Worksheet, and Commutative & Associative Crew Day 3 Cool Down.
- Prepare whiteboard or projector.
- Have counting objects available for students who may need them during the small group activity.
Step 1
Warm-up & Spiral Review (MD.4)
5 minutes
Project a spiral review question from the Commutative & Associative Crew Day 3 Slide Deck.
- Present a new data set (e.g., favorite colors).
- Ask students a 'how many more/less' question, encouraging them to explain their solution strategy.
Step 2
Review & Application of Properties (OA.3)
15 minutes
Use the Commutative & Associative Crew Day 3 Slide Deck and Commutative & Associative Crew Day 3 Script to guide instruction.
- Briefly review both the commutative and associative properties with quick examples.
- Present problems that can be solved more easily by applying these properties (e.g., 2+7+3, encourage (7+3)+2).
- Model how to 'look for friendly numbers' using these properties.
Step 3
Small Group Activity: Property Puzzle
30 minutes
- Divide students into small groups.
- Provide each group with the Commutative & Associative Crew Day 3 Worksheet.
- Instruct them to solve addition problems with three or more addends, actively looking for opportunities to use either the commutative (flipping) or associative (grouping) property to make adding easier.
- Circulate to provide support, prompt strategic thinking (e.g., 'Can you make a ten here?'), and encourage discussion among group members.
- Students should show their work, demonstrating which property they used.
Step 4
Cool Down/Exit Ticket
5 minutes
- Distribute the Commutative & Associative Crew Day 3 Cool Down to each student.
- Students complete a short problem demonstrating their understanding of applying one of the properties.
- Collect cool-downs to assess individual comprehension.
Slide Deck
Add It Up: Commutative & Associative Crew! Day 3
Today, we become TRUE addition superheroes by using our properties to solve tricky problems!
Welcome students and set the stage for applying what they've learned.
Warm-up: Favorite Colors!
Let's look at our class's favorite colors!
Blue šššššš
Green ššš
Red ā¤ļøā¤ļøā¤ļøā¤ļøā¤ļø
Question: How many more students like Blue than Green?
Display a simple pictograph/bar graph. Example:
Favorite Colors:
Blue: 6 students
Green: 3 students
Red: 5 students
Ask: "How many more students like Blue than Green?" or "How many less students like Green than Red?" Discuss strategies.
Quick Review: Commutative Property (Flip-Flop Facts!)
2 + 8 = 10
8 + 2 = 10
The order doesn't change the sum!
Briefly remind students about the commutative property. "Remember, 'Commutative' means we can flip the numbers and the sum is still the same!"
Quick Review: Associative Property (Grouping Gang!)
(1 + 4) + 5 = 10
1 + (4 + 5) = 10
The grouping doesn't change the sum!
Briefly remind students about the associative property. "And 'Associative' means we can change how we group the numbers when adding three or more, and the sum is still the same!"
Using Our Powers: Friendly Numbers!
Sometimes, using our Commutative and Associative powers can help us find friendly numbers!
Friendly numbers are numbers that are easy to add together, like numbers that make 10.
Example: What if you had to add 2 + 7 + 3?
Can we move them or group them to make adding easier?
Introduce the idea of 'friendly numbers'. Model an example like 2+7+3. Show how rearranging to 2+3+7 (commutative) and then grouping (2+3)+7 or 2+(3+7) can make it easier. Emphasize making a 10.
Solving With Friendly Numbers!
Let's try 2 + 7 + 3 again!
-
Flip! Can we move numbers to make a 10? Yes! Let's put 7 and 3 together.
2 + 3 + 7 -
Group! Now, let's group our friendly numbers!
(2 + 3) + 7 = 5 + 7 = 12 (Maybe not the easiest here)
OR
2 + (7 + 3) = 2 + 10 = 12! (Much easier!)
We used both properties!
Show the solution for the example 2+7+3. Highlight the steps: first commutative (7+3=10), then associative (grouping).
Your Mission: Property Puzzles!
Now, it's your turn!
Work in your groups to solve addition problems. Look for friendly numbers and use your Commutative (flip!) and Associative (group!) powers to make adding easier.
Show your work on the Commutative & Associative Crew Day 3 Worksheet!
Explain the small group activity. They will get a worksheet and practice applying both properties to make addition easier. Remind them to look for ways to make 10 or other friendly combinations.
Time to show what you know!
Complete the Commutative & Associative Crew Day 3 Cool Down on your own. Show how you used a property to solve it!
Explain the cool-down/exit ticket. Give each student the cool-down and instruct them to complete it individually.
Script
Commutative & Associative Crew: Day 3 Script
Welcome & Setting the Stage (0-1 minute)
"Good morning, Addition Crew! Today is the day we put all our amazing math detective skills to the test. We're going to use both the Commutative and Associative Properties to become true addition superheroes!"
Warm-up & Spiral Review (MD.4) (4-5 minutes)
"Let's start with a quick check-in on our data detective skills. Look at the screen ā it shows our class's favorite colors!"
(Display Commutative & Associative Crew Day 3 Slide Deck - Slide: Warm-up: Favorite Colors!)
"Based on this data, can you tell me: how many more students like Blue than Green? And how did you figure that out?"
(Pause for responses. Encourage students to explain their strategy, e.g., "I saw 6 blue hearts and 3 green hearts. 6 minus 3 is 3, so 3 more students like blue.")
"Excellent thinking! It's so important to be able to compare numbers and understand what our data is telling us."
Review & Application of Properties (OA.3) (15 minutes)
"Alright, let's do a super quick review of our two powerful addition properties. First, who can remind me about the Commutative Property? What's its special trick?"
(Listen for: "You can flip the numbers.", "The order doesn't change the sum.")
(Display Commutative & Associative Crew Day 3 Slide Deck - Slide: Quick Review: Commutative Property (Flip-Flop Facts!))
"Exactly! It's our 'Flip-Flop Fact'! Like 2 + 8 is the same as 8 + 2. Both give us 10!"
"Now, what about our other property, the Associative Property? What's its special power?"
(Listen for: "It's about grouping.", "You can change which numbers you add first.")
(Display Commutative & Associative Crew Day 3 Slide Deck - Slide: Quick Review: Associative Property (Grouping Gang!))
"Perfect! It's our 'Grouping Gang'! When we have three or more numbers, we can change which two we add first using those parentheses, and the sum stays the same. For example, (1+4)+5 is 5+5=10, and 1+(4+5) is 1+9=10! The answer is still 10!"
"Now, here's where it gets really exciting! We can use both of these properties to make adding easier, especially when we have lots of numbers. We can look for friendly numbers!"
(Display Commutative & Associative Crew Day 3 Slide Deck - Slide: Using Our Powers: Friendly Numbers!)
"Friendly numbers are numbers that are super easy to add, like numbers that make a 10. For example, 7 and 3 are friendly because they make 10!"
"Let's try this problem: 2 + 7 + 3."
(Display Commutative & Associative Crew Day 3 Slide Deck - Slide: Solving With Friendly Numbers!)
"Looking at 2, 7, and 3, do you see any friendly numbers that would be easy to add first?"
(Guide students to identify 7 and 3.)
"Yes! 7 and 3 make 10! But they're not next to each other right now. What property lets us flip the numbers around?"
(Wait for 'Commutative Property'.)
"That's right! The Commutative Property! So, we can rewrite it like this: 2 + 3 + 7."
"Now, we have our friendly 3 and 7 together. What property lets us group those numbers so we add them first?"
(Wait for 'Associative Property'.)
"You got it! The Associative Property! So, we can group them like this: 2 + (3 + 7). What is 3 + 7? (10) And what is 2 + 10? (12)! Wow, that was much easier than adding 2+7 first (which is 9), then 9+3 (which is 12). Both give us 12, but one way was much friendlier!"
Small Group Activity: Property Puzzle (30 minutes)
"Alright, Addition Superheroes! It's time for your mission: The Property Puzzle!"
(Display Commutative & Associative Crew Day 3 Slide Deck - Slide: Your Mission: Property Puzzles!)
"In your small groups, you'll get the Commutative & Associative Crew Day 3 Worksheet. Your job is to solve addition problems with three or more numbers. I want you to actively look for friendly numbers and then use either the Commutative Property (flipping) or the Associative Property (grouping) to make adding them easier."
"Show your work, explaining how you used the properties. Talk with your group members and help each other find the easiest way to solve!"
(Circulate, observe, and assist students. Prompt strategic thinking: "Can you make a ten here?", "Which numbers would you want to add first?", "How could you rearrange these to make it easier?", "Show me how you used a property.")
Cool Down/Exit Ticket (5 minutes)
"Excellent work today, everyone! To show me what you've learned, please complete this quick Commutative & Associative Crew Day 3 Cool Down on your own. Try to use one of our properties to solve the problem in the easiest way!"
(Distribute cool-down sheets and collect them after students have completed them.)
"You've done an amazing job applying these powerful math properties today!"
Worksheet
Commutative & Associative Crew: Day 3 Worksheet
Name: _________________________
Date: _________________________
Property Puzzle Challenge!
Directions: Solve these addition problems. Use the Commutative Property (flip the numbers) and the Associative Property (group the numbers with parentheses) to find friendly numbers and make adding easier! Show your steps.
Example: Solve 2 + 5 + 8
Thinking Time: I see that 2 and 8 are friendly numbers because they make 10! I can use the commutative property to move them together, then the associative property to group them.
Step 1 (Commutative Property): Flip the numbers to put 2 and 8 next to each other.
2 + 8 + 5
Step 2 (Associative Property): Group the friendly numbers.
(2 + 8) + 5
Step 3: Solve!
10 + 5 = 15
So, 2 + 5 + 8 = 15!
Problem 1: Solve 3 + 8 + 7
Show your work, using properties to find friendly numbers:
Answer: ____
Problem 2: Solve 4 + 9 + 1
Show your work, using properties to find friendly numbers:
Answer: ____
Problem 3: Solve 5 + 6 + 4
Show your work, using properties to find friendly numbers:
Answer: ____
Challenge Problem: Solve 1 + 5 + 2 + 9
Show your work, using properties to find friendly numbers:
Answer: ____
Cool Down
Commutative & Associative Crew: Day 3 Cool Down
Name: _________________________
Date: _________________________
Property Power Exit Ticket!
Directions: Solve the problem below. Show how you used either the Commutative Property (flipping numbers) or the Associative Property (grouping numbers) to help you solve it more easily.
Problem:
6 + 2 + 4 = ____
Show your steps and explain your thinking: