# Lesson 26

Book Drive (optional)

## Warm-up: Notice and Wonder: Books for Sale (10 minutes)

### Narrative

The purpose of this warm-up is to introduce the idea of a book sale, which will be useful when students work with this context in a later activity. While students may notice and wonder many things about these images, the range of and prices and types of books are the important discussion points.

### Launch

• Groups of 2
• Display the image.
• “What do you notice? What do you wonder?”
• 1 minute: quiet think time

### Activity

• 1 minute: partner discussion
• Share and record responses.

### Student Facing

What do you notice? What do you wonder?

### Activity Synthesis

• “What are some things we have to think about if we plan a book fair for our school?” (The different types of books we sell and have to order, the cost of the books for us, the amount to charge for each book, the number of people who come to the fair, and the number of books that we sell.)

## Activity 1: Book Prices (20 minutes)

### Narrative

In this activity students compare two book sale scenarios in which there is a different base price of a book for the fundraiser. Students notice that when you increase the price by a lot, you make more profit per book, but you may also sell fewer books. On the other hand, if you increase the price by less money, you have to sell more books to make the same profit.
MLR6 Three Reads. Keep books or devices closed. Display only the problem stem, without revealing the questions. “We are going to read this question 3 times.” After the 1st Read: “Tell your partner what this situation is about.” After the 2nd Read: “List the quantities. What can be counted or measured?” Reveal the question(s). After the 3rd Read: “What strategies can we use to solve this problem?”

### Launch

• Groups of 2
• “When a school plans a book sale fundraiser, the school orders books from the publisher, or bookseller, for a certain price. Then the school sells it for a different price at the book fair.”
• “Let’s imagine the school buys a book for \$10. Should they sell the book for more or less than \$10 at the book fair? Why?” (More if they want to make money from the sale.)
• “This is called the mark-up price. For every book they sell, the bookseller will get \$10 and the school keeps the amount they added. The amount they add is called the profit.” ### Activity • 1 minute quiet think time • 5 minutes: group work time • Monitor for students who consider the profit per book in their justifications. ### Student Facing Two schools buy science books for \$8 from a publisher to sell at their book sale. School A sells the books for \$12. School B sells the books for \$12.90.

1. Who do you think sells more science books? Why?
2. How much profit does each school make if they each sell 35 books?
3. School B sells 10 science books. How many science books does School A have to sell to raise about the same amount of money?

### Activity Synthesis

• “What is a reasonable mark-up price?”
• “What do you need to consider when deciding a mark-up price?”

## Activity 2: Plan a Book Fair (20 minutes)

### Narrative

In this activity students plan a school book fair. They choose the types of books to order and the cost for each type of book. They also estimate how many people might come to the book fair and how much money the school might raise through the book sale.

Students will have to make many assumptions in this activity: how many people are coming, how many books each person will buy, and how much to add to the price of the book, to name a few. When students are explicit about assumptions, they model with mathematics (MP4).

Engagement: Develop Effort and Persistence. Invite students to generate a list of shared expectations for group work. Record responses on a display and keep visible during the activity.
Supports accessibility for: Language, Social-Emotional Functioning, Organization

### Launch

• Groups of 2
• “In this activity, you’ll plan a book fair. The table shows the price list of each type of book from the publisher.”
• “Sometimes when we plan something like a book fair, we make assumptions. Assumptions are things we think will be true based on our experiences, but they might not always be. For example, we can make assumptions about who might come to the book fair.”
• “Who might come to the book fair and buy books?” (students, parents, grandparents, friends)
• As you plan the book fair, think about other assumptions you make, how they affect the book fair, and how to communicate them in your work.

### Activity

• 1–2 minutes: quiet think time
• 10–12 minutes: partner work time
• Monitor for students who:
• Select the types of books based on the kinds of attendees. For example, they select history books because that is something parents want and chapter books which are preferred by students.
• Make assumptions about the number of attendees and the number of each type of book sold.

### Student Facing

Price list from the publisher:

Plan a book fair:

type of book price
boxed sets & collections \$24.95 comic books \$2.60
science books \$8.00 chapter books \$9.99
history books \$14.49 audiobooks \$20.00
activity books \$4.50 reference books \$12.00
Spanish language books \$6.00 biographies \$6.05
1. Choose 3–5 types of books you want to order.
2. Decide on the mark-up price for each type of book you chose.
3. Estimate the amount of money your school will raise as a profit with your book sale.

Record an estimate that is:

too low about right too high
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4. Show or explain your reasoning for the estimate. Include the assumptions you made.

### Activity Synthesis

• Invite students to share their book sale plans.
• Invite students to share their assumptions.
• “Why did you make these assumptions?” (There are 600 students, so I thought that maybe only half would come since that is usually what happens. Since the school wants to make a profit, but also make the books affordable, the mark-up price is only one more dollar than the list price.)

## Lesson Synthesis

### Lesson Synthesis

“Today, you planned a book fair and made assumptions to make decisions about the book fair.”

“How did the assumptions you made affect your plan or the money raised at the book fair?” (I picked the kinds of books to sell based on the people I thought would come. I assumed everyone who came would buy at least one book. I assumed that half of the students from the school would come. This helped me decide how to price the books so we can raise the most money without making the books too expensive.)