Lesson 21
Classroom Supplies (optional)
Warmup: Notice and Wonder: School Supplies List (10 minutes)
Narrative
The purpose of this warmup is to elicit observations about school supplies in different categories and with varying prices, familiarizing students with the context for upcoming work. While students may notice and wonder many things, focus the discussion on the large selection and wide range of prices.
Launch
 Groups of 2
 Display the table.
 “What do you notice? What do you wonder?”
 1 minute: quiet think time
Activity
 “Discuss your thinking with your partner.”
 1 minute: partner discussion
 Share and record responses.
Student Facing
What do you notice? What do you wonder?
work supplies  cost 

box of 25 markers  $5 
box of 100 crayons  $8 
class library  cost 

set of 20 books about history  $250 
story book (80 to choose from)  $8 
special items  cost 

carpet for the reading corner  $65 
a class aquarium, with fish  $159 
entertainment  cost 

board games (40 to choose from)  $15 
interactive computer games (math and reading)  $75 
Student Response
Teachers with a valid work email address can click here to register or sign in for free access to Student Response.
Activity Synthesis
 “If you had to pick one item from this list for our classroom, what would you pick?”
 “What is one other thing you would like to get for our classroom that is not on this list?”
 30 seconds: quiet think time
 Share and record responses.
Activity 1: Make a Wish List (25 minutes)
Narrative
The purpose of this activity is for students to make a wish list of items for the classroom with a $1,000 budget. As they make their selections, they keep an estimate of the total by rounding, and use estimation and addition strategies to remain within the budget. To make their wish list, students use a supply list that is longer than shown in the warmup.
Supports accessibility for: Organization, Conceptual Processing
Launch
 Groups of 2
 “Imagine our class got a donation of \$1,000 to spend on anything we’d like from the list.”
 “Today you will get to decide how to spend \$1,000. As you make your choices, estimate or round to keep track of your total until you get close to \$1,000.”
Activity
 2 minutes: independent work time
 1012 minutes: partner work time
 Monitor for a variety of addition strategies students use to keep track of their budget.
 Monitor for students who:
 round to the nearest ten
 round before multiplying or round after multiplying the quantity
 revise their list if they were under or over budget
Student Facing
Imagine our class received $1,000 to spend on school supplies from the given list. How would you spend the money to benefit our classroom the most?
work supplies  cost 

box of 25 markers  $5 
box of 100 crayons  $8 
box of 60 pencils  $5 
box of 5,000 pages of printer paper  $40 
package of 10 pads of lined paper  $15 
box of 50 pieces of construction paper  $32 
class library  cost 

set of 20 books about history  $250 
set of books about nature  $400 
story book (80 choices)  $8 
maps (5 choices: world, continent, North America, U.S. state, U.S. city)  $45 
special items  cost 

carpet for the reading corner  $65 
a class aquarium, with fish  $150 
fish food for one month  $15 
field trip to the zoo  $350 
entertainment  cost 

puzzles (30 choices)  $12 
board games (40 choices)  $15 
interactive computer games (math and reading) 
$75 
 Make a plan on how to spend the money. You may purchase more than one of the same item. Use estimation or rounding to keep track of the total as you make your selections.

On your wish list, what is the total cost of the items in each category?
 Supplies
 Books and maps
 Puzzles and games
 Special items

What was the total cost of all your choices?
 Would you have any money left over? If so, how much?
 Did you spend too much money? If so, how much?
Student Response
Teachers with a valid work email address can click here to register or sign in for free access to Student Response.
Activity Synthesis
 Invite previously selected students to share why they made revisions to their wish list.
 “Turn and talk: How did you make your choices?” (Rationale can go beyond the cost of items, such as students liking a specific item or stating the need for an item.)
 Share responses.
 “Did your actual cost go over the $1,000 or stay under?”
 “Did rounding affect whether your actual costs were over or under $1,000? If so, how?” (My rounding made my actual cost stay under because I rounded up a lot when I estimated the cost. My actual cost went over because I rounded down a lot.)
Activity 2: What's on Your List? (15 minutes)
Narrative
In this activity, students present their selections to a partner group. They explain their choices and compare how much money they plan to spend in each category. They make comparisons using “how much more” and “how much less” statements.
Advances: Speaking, Representing
Launch
 Groups of 2
 “Now, share your wish lists with another partnership. Take turns sharing what you chose and explain the choices you made.”
 Pair each group with another group to share.
Activity
 1012 minutes: smallgroup work time
 Monitor for “more than” and “less than” language when students make comparisons.
Student Facing
 Share your wish list with another group. Take turns to explain how you made your choices and listen to the choices of the other group.

Compare your spending:
 How much more or less did you choose to spend on each category than the other group?
 How much more or less did you spend in total compared to your partner group?
Student Response
Teachers with a valid work email address can click here to register or sign in for free access to Student Response.
Activity Synthesis
 Invite groups to share how their strategies compared to those of their partner groups.
 Invite partner groups to share their comparisons with the whole class using “how much less” and “how much more” statements.
Lesson Synthesis
Lesson Synthesis
“Today, we made decisions to buy helpful and beneficial materials for the class. Unfortunately, there wasn’t enough money to buy everything on the list.”
“What else would you get if we had more money?”
“Which item on the list has the greatest benefit for the class?” (I think the fish would have the most value because we get to learn about science as we take care of the fish and how to be responsible for a pet.)
Consider asking, “What are some other things you would buy for the class that are not on the list?”