Center for Mathematical Professional Learning and Educational Technology

Category: Proportional Reasoning

World’s Largest Cookie

World’s Largest Cookie

Grade: 3-8

The world’s largest chocolate chip cookie was created using 40,000 pounds of cookie dough! (The recipe is listed below.)

A school wants to make a smaller version of this cookie to feed all 800 students in their school. They decide that each pound of dough will feed 4 students.

How many pounds of chocolate chips will they need?

Anticipatory Set
Lesson Plan
Black Line Master

Watermelon

Watermelon

Grade: 3-8

A giant watermelon weighed 100 pounds and was 99 percent water. While sitting in the sun, some of the water evaporated. Now, the watermelon is only 98 percent water. How much does the watermelon weigh now?

Anticipatory Set
Lesson Plan
Black Line Master

Solar Power City

Solar Power City

Grade: 3-8

Solar panels collect energy from the sun so people can use that energy to power things in their homes.

Is it possible to power an entire city by using only solar energy?

New York City uses about 164,380 kilowatt hours of electricity each day. Usually, it takes 25 solar panels to produce about 5 kilowatt hours of electricity. How many solar panels would it take to power all of New York City for one day?

Anticipatory Set
Lesson Plan
Black Line Master

Eucalyptus

Eucalyptus

Grade: 3-8

99% of the trees in our neighborhood are eucalyptus trees. The town planning commission wants to get rid of some of these trees because they spread too quickly. However, the people in my neighborhood like the trees. The commission argues that their new eucalyptus tree removal plan will cut down so few eucalyptus trees that 98% of the trees in our neighborhood will be eucalyptus trees. If the plan only involves removing eucalyptus trees, what percent of the existing tress in my neighborhood would the plan remove?

Anticipatory Set
Lesson Plan
Black Line Master

Bubble Gum

Bubble Gum

Grade: 3-8

Have you ever wondered why gum loses its sweetness so quickly? Does it seem like the gum gets smaller after you chew it? Well, sugar contributes to gum’s flavor. During chewing, the sugar is lost, which makes the gum get smaller as it loses sweetness.

Anticipatory Set
Lesson Plan
Black Line Master

An apple A Day

An Apple a Day

Grade: 3-8

Have you ever heard someone say, “An apple a day keeps the doctor away”? At a
local grocery store, you can buy a bag of 8 apples for $5.00. If everyone in your
family ate one apple every day, how much money would your family spend in one
year on apples?

Anticipatory Set
Lesson Plan
Black Line Master