1. Launch
Abby and Zack are mixing red and yellow paint to make an orange color to paint their kitchen table. They each think they have the perfect shade of orange.
(Time on this slide – 1 min) Time passed 7 min
In-Class Notes
Brief introduction
Preparation Notes
This begins the narrative of Abby and Zack that continues throughout the next lesson.
Agenda

2. Launch Zack’s orange paint is made by mixing
3 cups of red for every 5 cups of yellow.
This sounds like a ratio.
What are ratios again?
(Time on this slide – 1 min) Time passed 8 min
In-Class Notes
Let students think for a moment about what a ratio is.
You could even do a Think, Pair, Share if time permits.
Preparation Notes
This sets up a review of vocabulary.
Agenda

3. Launch Here’s the definition:
A ratio is a relationship between two or more quantities.
But, why would I want to use or think about a ratio?
Here’s a short video that will show how ratios are used in a few real life situations. 
(Time on this slide – 2 min) Time passed 10 min
In-Class Notes
Make sure students have the definition for a ratio in their notes somewhere. Acceptable if they can turn to it from prior lesson.
Click “www” symbol for link to video.
Reflection questions on video follow.
Preparation Notes
Clicking the internet symbol will bring you to a very short video clip (1:19) you can play that will show students how ratios are used in a variety of jobs.
Agenda

4. Launch – Think, Pair, Share
Zack’s orange paint is made by mixing
3 cups of red for every 5 cups of yellow.
A’s – Tell B’s the ratio of red to yellow in Zack’s orange paint.
3:5
B’s – Tell A’s the ratio of yellow to red in Zack’s orange paint.
Class – What is the ratio of red to yellow in Zack’s orange paint?
Partner Share
(Time on this slide – 2 min) Time passed 14 min
In-Class Notes
Students should see that 3:5 is a different ratio than 5:3 and to make sure to read carefully.
Preparation Notes
Anytime students take time to talk to each other about the content you are increasing the language usage and helping your ELL students.
3 to 5
or 3:5
or 3 5
Agenda

5. 3:5 Explore – Strategize Zack bought 24 cups of red paint.
How much yellow paint will Zack need to buy to make his shade of orange paint?
3:5
Write down in your notes any ideas you have about how to answer this question.
(Time on this slide – 1 min) Time passed 15 min
In-Class Notes
Students are NOT meant to solve this problem before the lesson. This slide is a preview of the overarching question that gives students a clear need for the Tape Diagrams tool.
The teacher may want to point out or highlight from any student questions that Zack’s original ratio is 3 red to 5 yellow.
Some students may get the answer right away. Some may only write down the question. That’s ok. The point is to establish a need for the tape diagram tool. They will all have to prove the answer using the tool for the exit ticket. Let speedy students know this. “Nice work. We are going to learn about a way to visually show how you get this answer. It’s a pretty nice tool for ratio problems – I really think you will like it.” For students who don’t know how to begin, “I see that you are struggling with your strategy for this problem. Lucky for you we are going to learn a really helpful tool for solving this problem. I really think you will like it.” 
Agenda

6. Explore – Mini-Lesson
Before we solve Zack’s problem, let’s look at some simpler problems to get ready. Read this problem.
Example 1) The ratio of boys to girls in a class is 2 to 3.
1. If there are 4 boys in the class, how many girls are there?
(Time on this slide – ½ min) Time passed 16 min
In-Class Notes
Students are NOT solving this problem. It is an example used to illustrate the tape diagrams tool.
Click through to get to the heart of the lesson: the introduction to the tape diagram
Preparation Notes
You will want to spend a good deal of preparation time reviewing the next slides so that you thoroughly understand how a tape diagram is created and used. Drawing an accurate model is very important.
Agenda

7. Explore – Mini-Lesson
Let’s learn about a helpful tool for ratio problems that could help you with all sorts of ratio problems.
Example 1) The ratio of boys to girls in a class is 2 to 3.
1. If there are 4 boys in the class, how many girls are there?
(Time on this slide – ½ min) Time passed 16 min
In-Class Notes
We want students to be very clear that there are several very useful tools for working with ratios. The tape diagram is the first of these tools that they will learn about.
Preparation Notes
This lesson is an introductory lesson for students on a visual model for ratio problem solving called here, the tape diagram. It is also referred to as a “unit bar model” in Singapore Mathematics. Many high-achieving countries use this visual model for ratio problem solving.
Students can just watch the diagram creation without writing anything unless your students have trouble with this kind of instruction. Then have students draw the diagram with you. This will obviously take more time and require the lesson to be broken into 2 days.
Agenda

8. New Tool: Tape Diagram
Explore – Mini-Lesson
We can use a tape diagram to solve ratio math problems.
Example 1) The ratio of boys to girls in a class is 2 to 3.
boys
girls
Each box represents a number in the original ratio.
1. If there are 4 boys in the class, how many girls are there?
(Time on this slide – 3 min) Time passed 19 min
In-Class Notes
Go slowly and make sure that students realize that the “4 boys” in the problem belongs written above or below the appropriate tape.
Now let’s look at the question.
Agenda

9. New Tool: Tape Diagram
Explore – Mini-Lesson
We can use a tape diagram to solve ratio math problems.
Example 1) The ratio of boys to girls in a class is 2 to 3.
If this tape shows 4 boys then…
boys
girls
1. If there are 4 boys in the class, how many girls are there?
(Time on this slide – 1 min) Time passed 20 min
In-Class Notes
Make sure they see that the first step is to set up the tape diagram with information that is given to us. This can take time but it is time well-spent.
Agenda

10. New Tool: Tape Diagram
Explore – Mini-Lesson
We can use a tape diagram to solve ratio math problems.
Example 1) The ratio of boys to girls in a class is 2 to 3. 4
How many students are in one box?
This tape is 4 boys.
So we put 4 above the tape. 2 2
boys
girls 2
1. If there are 4 boys in the class, how many girls are there?
(Time on this slide – 2 min) Time passed 22 min
In-Class Notes
This slide can be replayed over and over to show students how we get to “2” in each box. You distribute the 4 into the two boxes in the tape.
Agenda

11. The number in each box must be the same for every tape.
New Tool: Tape Diagram
Explore – Mini-Lesson
We can use a tape diagram to solve ratio math problems.
Example 1) The ratio of boys to girls in a class is 2 to 3. 4
We don’t yet know the number of girls so we put a ? for the length of that tape. 2 2
Important Rule:
The number in each box must be the same for every tape.
boys 2 2 2
girls ?
1. If there are 4 boys in the class, how many girls are there?
(Time on this slide – 1 min) Time passed 23 min
In-Class Notes
Very important rule. This is the key to students being able to recreate and use a tape diagram.
Preparation Notes
Make sure you spend time to make sure you fully understand the model and how to explain it.
Agenda

12. New Tool: Tape Diagram
Explore – Mini-Lesson
We can use a tape diagram to solve ratio math problems.
Example 1) The ratio of boys to girls in a class is 2 to 3. 4 2 2
Now we can answer the question.
boys 2 2 2
girls ?
1. If there are 4 boys in the class, how many girls are there?
(Time on this slide – 1 min) Time passed 24 min
In-Class Notes
If you use the tool correctly it is extremely simple to find the answer to the question asked. 6
Agenda

13. ? 8 Explore – Mini-Lesson Let’s try another one.
New Tool: Tape Diagram
Explore – Mini-Lesson
Let’s try another one.
Example 2) The ratio of boys to girls in a class is 3 to 2. ?
We can label what we know. 8 girls.
boys
girls
First, draw the tapes.
We can put a question mark for what we don’t know. 8
2. If there are 8 girls in the class, how many boys are there?
(Time on this slide – 2 min) Time passed 26 min
In-Class Notes
Make sure students realize that this is a different problem.
Now let’s look at the question.
Agenda

14. 4 ? 8 Explore – Mini-Lesson Let’s try another one.
New Tool: Tape Diagram
Explore – Mini-Lesson
Let’s try another one.
Example 2) The ratio of boys to girls in a class is 3 to 2. ?
How many students does each box represent?
boys
This makes 8 girls. 4 4
girls 4 8
2. If there are 8 girls in the class, how many boys are there?
(Time on this slide – 2 min) Time passed 28 min
In-Class Notes
Again, here is a very important step. If there are 8 girls and the ratio indicates we must make 2 boxes for a ratio of 3:2 then we can distribute the 8 into the 2 boxes.
Students may, of course, realize this “distribution” as division. This would be desired but does not need to be pushed early.
Agenda

15. Every box must have the same quantity.
New Tool: Tape Diagram
Explore – Mini-Lesson
Let’s try another one.
Example 2) The ratio of boys to girls in a class is 3 to 2. ?
Remember:
Every box must have the same quantity.
boys 4 4 4 4 4
girls 8
2. If there are 8 girls in the class, how many boys are there?
(Time on this slide – 2 min) Time passed 30 min
Preparation Notes
Advanced box comes as a click at the end of this slide. Use if you want to. 12
Can you answer the question using the diagram?
Advanced: Think of one way you could prove that the numbers in each box should be 4. Tell your partner.
Agenda

16. New Tool: Tape Diagram
Let’s solve this problem using a tape diagram.
The question is: How many cups of yellow paint does Zack need to make his shade of orange paint?
We know: Zack’s orange paint is made by mixing
3 cups of red for every 5 cups of yellow.
And, we know: he bought 24 cups of red paint.
Since every box must have the same quantity…
Now we can figure out how many cups each box represents. If 3 boxes are 24 then…
This is a 3:5 ratio of red to yellow. 24
Let’s label the diagram.
red
yellow 8 8 8
Let’s draw the tapes. 8 8 8 8 8
(Time on this slide – 1 min) Time passed 85 min
In-Class Notes
For the exit ticket it is important that students make a tape diagram to prove that they have mastered the objective for the lesson. ?
40 cups of yellow paint
That means the answer is:
Agenda

17. Summary – Write in your notebook
What is one thing you like about the tape diagrams as a tool?
What is one thing that is difficult?
Is there anything that is confusing about using tape diagrams as a tool?
(Time on this slide – 5 min) Time passed 80 min
In-Class Notes
Have students take 3-5 minutes to write sentences that answer these three questions.
Select 3 students at random to answer one of the questions by reading their writing.
Agenda

18. Practice
You will have 10 minutes to work on solving some ratio problems using the tape diagrams tool. You might feel a little confused and want to talk about it.
Don’t worry – you will discuss it when you are finished.
(Time on this slide - 15 min) Time passed 50 min
In-Class Notes
This screenshot is a cue for students so that they know what page to have in front of them.
Answers will be provided later in the slideshow.
Agenda