Ratio and Proportion
Valesta Cobbs John Fiske Elementary School
6145 S. Ingleside Ave.
Chicago IL 60637
(312)535-0990
Objectives:
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)
Timer
Strategy:
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.
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