Sweet Sums Slides
Year 1 Addition & Subtraction
SWEET SUMS
Swap the Treats & Solve the Mystery!
Let's learn how swapping our groups works for addition... but does it work for subtraction?
Commutative Addition & The Subtraction Mystery
Slide 1 of 8
Our Math Mission
L.O.
Learning Goal
We are learning to see how swapping our groups gives the same total in addition, and investigate if this works for subtraction!
Steps to Success:
1
I can swap the order of my addition groups.
2
I can see that the addition total stays the same.
3
I can test if swapping groups works for subtraction!
Get Ready to Tell Stories!
Slide 2 of 8
Concept Spark
🍪 The Cookie Flip! 🍪
Look at these yummy chocolate chip cookies on our plates. Let's see what happens when we swap them!
STORY A
3 + 2 = 5
SWAP!
STORY B
2 + 3 = 5
The total cookie count is still 5! Changing the order did not change our total!
Commutative Addition is like a magic mirror!
Slide 3 of 8
Teacher Model: I Do
The Story
Apple Adventures!
Miss Sarah put 4 green apples on a plate. Then, she added 3 red apples.
Let's count how many we have altogether, then let's swap them around!
Teacher Note:
Point out to students that regardless of which color apple we count first, the combined basket has the exact same quantity.
First Story
4 + 3 = 7
Swapped!
3 + 4 = 7
Watch the teacher explain the green and red apple swap.
Slide 4 of 8
Guided Practice: We Do
Let's Try Together!
Cupcake Carousel!
There are 5 pink cupcakes and 2 purple cupcakes on a tray.
How do we write this story as TWO addition sentences?
Let's Talk:
Which cupcakes should we count first? Let's count pink first. Now let's count purple first. What changed? What stayed the same?
Pink First
5 + 2 = 7
Purple First
2 + 5 = 7
Can you say both addition sentences out loud?
Slide 5 of 8
Math Mystery: Part 1
11 Bees in the Garden!
Listen to this subtraction story: There were 11 busy bees buzzing in the garden. Suddenly, 7 bees flew away!
How many bees stayed in the garden?
!
Let's Act It Out!
We need 11 student bees to buzz up to the front.
Now, 7 bees fly away back to their seats. Count the remaining bees!
Recorded Equation
11 − 7 = 4
Act out starting with 11 and taking away 7.
Slide 6 of 8
Math Mystery: Part 2
The Great Swap?
I wonder if our magic addition "swap-the-order" property works for subtraction too!
Let's change the position of the 11 and the 7 in the equation:
11 - 7 = 4 ➔ 7 − 11 = ?
Let's Try It!
Start with only 7 student bees standing at the front.
Now, try to have 11 of those bees fly away! Can you do it?
We don't have enough bees! We can't take away 11 from 7!
Our Conjecture!
Conjecture: The commutative property does NOT work for subtraction!
But wait! One example is not enough evidence to be absolutely sure. We will need to investigate further!
Can we subtract 11 from 7? No! Subtraction is different!
Slide 7 of 8
Independent Challenge: You Do
You Got This!
Cherry Sparklers!
Look closely at these cherries. There are 6 bright red cherries and 3 sweet golden yellow cherries.
Whisper the two commutative math equations to your neighbor!
Worksheet Companion Time!
Next, you will get your very own sheet to draw your own food, write your equations, and test our subtraction mystery!
First:
6 + 3 = 9
Swap:
3 + 6 = 9
Incredible! You are ready to draw your own stories!
Slide 8 of 8
Draw Your Story Worksheet
Year 1 Math Companion
Name: ______________________ Date: ____________
🍬 Draw Your Own Story!
Math stories are magic! When we swap our groups of treats, our total stays exactly the same. Let's practice drawing and writing our equations!
Warm-Up Example:
2 chocolate cookies + 3 strawberry cookies = 5 cookies. Swap them: 3 strawberry + 2 chocolate = 5 cookies!
1
Guided Story: Cupcake Party!
Your Mission: Draw 4 pink cupcakes on Plate A, and 3 blue cupcakes on Plate B.
Plate A (Draw 4 Pink)
Plate B (Draw 3 Blue)
Write both addition sentences:
First: + =
Swapped: + =
Unit: Commutative Addition Page 1 of 3
My Creative Story
Name: ______________________ Date: ____________
🎨 Create Your Own Cafe Story!
Now it is your turn to be the baker! Choose two sweet treats (such as cookies, cherries, or apples). Choose your numbers (up to 10 total) and draw them in the plates.
My Treat 1: ______________________
My Treat 2: ______________________
First Group (Draw Here)
Second Group (Draw Here)
Write the two addition sentences for your cafe story:
SWAP!
Unit: Commutative Addition Page 2 of 3
The Bee Investigation
Name: ______________________ Date: ____________
🐝 The Subtraction Swap Test!
Does the commutative "swap" property work for subtraction stories? Let's investigate together!
Part 1: 11 Bees - 7 Fly Away
Start with 11 bees in the box. Cross out 7 of them. How many are left?
Draw 11 bees & cross out 7
11 − 7 =
Part 2: The Subtraction Swap!
Start with only 7 bees in the box. Can you cross out 11? Try it!
Draw 7 bees. Try to cross out 11!
7 − 11 = Impossible!
Our Scientific Math Conjecture!
Because we cannot take away 11 bees when we only start with 7, we suspect that the swapping commutative property does NOT work for subtraction.
Do you think this is true for all subtraction? Circle your guess: Yes, never swap! or No, maybe it works sometimes!
My Self-Check: How did I do?
I can draw addition swap stories!
I can write commutative equations!
I investigated the bee mystery!
