Teacher Script: Fraction Fiesta: Unlike Denominators

Warm-up & Introduction (2 minutes)

Teacher: "Hi there! Today, we're going on a fraction adventure to solve some tricky problems. We're going to learn how to add and subtract fractions even when they have different-sized pieces!"

Teacher: "First, can you remind me, what is a fraction? What does the bottom number, the denominator, tell us?"

Teacher: "Great! Now, what do you think makes adding or subtracting fractions tricky when the bottom numbers (denominators) are different? Why can't we just add or subtract the top numbers right away?"

Teacher: "Exactly! It's like trying to add apples and oranges. We need to make sure we're talking about the same kinds of pieces. And today, we're going to use models to help us do just that!"

Modeling Addition (5 minutes)

(Display Fraction Fiesta Slide Deck - Slide: "Adding Fractions: Different Denominators?")

Teacher: "Look at this slide. It says, 'When we add fractions, we need parts of the same size.' And we'll use models to help us make them the same. Let's try our first problem."

(Display Fraction Fiesta Slide Deck - Slide: "Let's Add: 1/2 + 1/4")

Teacher: "Here's our problem: 'One day, you ate 1/2 of a pizza. The next day, you ate 1/4 of the same pizza. How much pizza did you eat in total?'"

Teacher: "Let's imagine this with our fraction models (or draw on the board). First, how would you show 1/2 of a pizza?"

(Draw or place a model showing 1/2. Then ask about 1/4.)

Teacher: "And how would you show 1/4 of a pizza?"

(Draw or place a model showing 1/4.)

Teacher: "Now, look at these two models. Are the pieces the same size? Can we just add them as they are?"

Teacher: "No, not yet! We need to make them the same size. Can we easily turn our half into quarters? How could we do that visually?"

(Guide student to see that 1/2 can be divided into two 1/4 pieces.)

Teacher: "That's right! If we split our 1/2 piece in half, we get two 1/4 pieces. So, 1/2 is the same as 2/4. Now we have 2/4 from the first day and 1/4 from the second day. How many quarters do we have altogether?"

Teacher: "Excellent! 2/4 + 1/4 = 3/4. So you ate 3/4 of the pizza. The models helped us see how to make the pieces equal!"

Modeling Subtraction (5 minutes)

(Display Fraction Fiesta Slide Deck - Slide: "Subtracting Fractions: Different Denominators!")

Teacher: "Now, let's try subtraction. It's very similar to addition because we still need those pieces to be the same size. This slide asks, 'How can models help us see what's left?' Let's find out!"

(Display Fraction Fiesta Slide Deck - Slide: "Let's Subtract: 3/4 - 1/2")

Teacher: "Our next problem is: 'You had 3/4 of a chocolate bar. You gave away 1/2 of the chocolate bar to a friend. How much chocolate bar do you have left?'"

Teacher: "First, how would you represent 3/4 of a chocolate bar using our models?"

(Draw or place a model showing 3/4.)

Teacher: "And how about the 1/2 you gave away?"

(Draw or place a model showing 1/2.)

Teacher: "Again, the pieces are different sizes. Can we easily subtract 1/2 from 3/4 right now?"

Teacher: "No. So, what could we do to our 1/2 model to make the pieces the same size as our 3/4?"

(Guide student to see that 1/2 can be divided into two 1/4 pieces.)

Teacher: "You got it! 1/2 is equivalent to 2/4. So, we started with 3/4 and we're taking away 2/4. If you have three quarters and you take away two quarters, what are you left with?"

Teacher: "That's right! 3/4 - 2/4 = 1/4. You have 1/4 of the chocolate bar left. The models helped us visualize taking away parts of the same size!"

Independent Practice & Check for Understanding (3 minutes)

(Display Fraction Fiesta Slide Deck - Slide: "Your Turn! Practice Time!")

Teacher: "You've done a great job understanding how to use models. Now it's your turn to practice on your own. Here's your Fraction Model Worksheet."

(Hand out the Fraction Model Worksheet.)

Teacher: "Please complete problem #1 (addition) and problem #2 (subtraction) on this worksheet. Remember to draw or use models to show your work, just like we did together."

(Observe the student working, providing gentle guidance if needed.)

Teacher: "Alright, let's check your work!"

(Review problems using the Fraction Model Answer Key. Address any misconceptions immediately, using models as needed.)

Teacher: "You did a fantastic job today using models to add and subtract fractions with different denominators! Keep practicing, and you'll be a fraction master in no time!"

Fraction Fiesta: Model It Out!

Instructions: For each problem below, draw models (like circles or rectangles) to help you solve the addition or subtraction problem. Make sure your models show how you found a common denominator!

1. Adding Fractions

You are baking a cake. You use 1/3 cup of flour and then realize you need more, so you add another 1/6 cup of flour. How much flour did you use in total?

Draw your models here:

Your Answer:

2. Subtracting Fractions

Your water bottle was 7/8 full. You drank 1/4 of the water. How much of your water bottle is still full?

Draw your models here:

Your Answer:

3. Challenge Problem (Optional)

You have 2/3 of a pie. Your friend eats 1/6 of the original whole pie. How much of the pie do you have left?

Draw your models here:

Your Answer:

Fraction Fiesta: Model It Out! - Answer Key

1. Adding Fractions

Problem: You are baking a cake. You use 1/3 cup of flour and then realize you need more, so you add another 1/6 cup of flour. How much flour did you use in total?

Thought Process:

1. Understand the fractions: We have 1/3 and 1/6.
2. Represent with models: Draw two identical rectangles or circles. Divide one into 3 equal parts and shade 1 part for 1/3. Divide the other into 6 equal parts and shade 1 part for 1/6.
   • Model for 1/3: [][][]
     • First box shaded
   • Model for 1/6: [][][][][][]
     • First box shaded
3. Find a common denominator using models: Look at the 1/3 model. Can we divide its parts to match the 1/6 model? Yes, each 1/3 piece can be divided into two 1/6 pieces.
4. Convert 1/3 to sixths: By dividing each third into two, 1/3 becomes 2/6.
   • Converted Model for 1/3 (now 2/6): [][][][][][]
     • First two boxes shaded
5. Add the fractions: Now we have 2/6 + 1/6.
6. Count the shaded parts: We have a total of 3 shaded parts out of 6.
7. Simplify (if necessary): 3/6 simplifies to 1/2.

Answer: You used 1/2 cup of flour in total.

2. Subtracting Fractions

Problem: Your water bottle was 7/8 full. You drank 1/4 of the water. How much of your water bottle is still full?

Thought Process:

1. Understand the fractions: We have 7/8 and 1/4.
2. Represent with models: Draw two identical rectangles or circles. Divide one into 8 equal parts and shade 7 parts for 7/8. Divide the other into 4 equal parts and shade 1 part for 1/4.
   • Model for 7/8: [][][][][][][][]
     • First seven boxes shaded
   • Model for 1/4: [][][][]
     • First box shaded
3. Find a common denominator using models: Look at the 1/4 model. Can we divide its parts to match the 7/8 model? Yes, each 1/4 piece can be divided into two 1/8 pieces.
4. Convert 1/4 to eighths: By dividing each quarter into two, 1/4 becomes 2/8.
   • Converted Model for 1/4 (now 2/8): [][][][][][][][]
     • First two boxes shaded
5. Subtract the fractions: Now we have 7/8 - 2/8.
6. Count the remaining shaded parts: Start with 7 shaded 1/8 pieces. Take away 2 shaded 1/8 pieces. You are left with 5 shaded parts out of 8.

Answer: Your water bottle is 5/8 full.

3. Challenge Problem (Optional)

Problem: You have 2/3 of a pie. Your friend eats 1/6 of the original whole pie. How much of the pie do you have left?

Thought Process:

1. Understand the fractions: We have 2/3 and 1/6.
2. Represent with models: Draw two identical circles or rectangles. Divide one into 3 equal parts and shade 2 parts for 2/3. Divide the other into 6 equal parts and shade 1 part for 1/6 (this is the amount to be subtracted).
   • Model for 2/3: [][][]
     • First two boxes shaded
   • Model for 1/6 (amount to subtract): [][][][][][]
     • First box shaded
3. Find a common denominator using models: Convert 2/3 to sixths by dividing each third into two pieces. 2/3 becomes 4/6.
   • Converted Model for 2/3 (now 4/6): [][][][][][]
     • First four boxes shaded
4. Subtract the fractions: Now we have 4/6 - 1/6.
5. Count the remaining shaded parts: Start with 4 shaded 1/6 pieces. Take away 1 shaded 1/6 piece. You are left with 3 shaded parts out of 6.
6. Simplify: 3/6 simplifies to 1/2.

Answer: You have 1/2 of the pie left.