Return to Mathematics IndexRatio and Proportion

Valesta Cobbs John Fiske Elementary School

6145 S. Ingleside Ave.

Chicago IL 60637

(312)535-0990Objectives:

The students will use the phenomenological approach to complete the

activities, calculate ratios and proportions and compare and contrast group data

with class data.Materials Needed:

Four 16 oz. bags of candy

Rice (2 different amounts of the same brand)

Cereal (2 different amounts of the same brand)

Tuna (2 different amounts of the same brand)

Canned Corn (2 different amounts of the same brand)

Gum (2 different amounts of the same brand)

Canned beans (2 different amounts of the same brand)

6 sets of 10 ratio cards with easily identifiable items to be

compared (For example: girls to boys)

TimerStrategy:

Review the definition of a ratio. Ask the students to write the number of

vowel letters and consonant letters in their name as a ratio of vowels to

consonants on a sheet of paper. Ask three or four students to come to the board

and write their name and the ratio of vowels to consonants.

Divide the class into groups of five. Give each group ten ratio cards.

Explain the directions and set the timer for five minutes. After the elapsed

time, tell the students to stop. Ask one student from each group to write the

group data on the board. Have the students line up on opposite sides of the

room according to the ratio. For example, if the students identify the ratio of

boys to girls, then the girls will line up in the front of the room and the boys

will line up in the back of the room. Have one student count the number of boys

and girls and check the answer on the board to make sure that it corresponds to

the numbers counted.

Review the definition of proportion. Give each group a bag containing at

least 10 pieces of candy. Clearly mark or label the price of the bag of candy.

Ask the students to find the cost of one piece of candy. Have a student from

each group record the group data on the board. Ask a member of each group to

orally state the unit price of one piece of candy in the bag of the group. Ask

the class to determine if the data written on the board is correct.

Give each group two different amounts of the same product. Ask the

students to determine the cost of one ounce of each product and the best buy.

Select one member of each group to write the group data on the board. Ask a

member of each group to explain the data written on the board for that group.

Have the class check the data written on the board.Performance Assessment:

Give each group two different amounts of another product. Ask the group to

determine the cost of one ounce of the product and the best buy.