**Fickled Fractions**

Elizabeth Chambers Keller Gifted Magnet Center

3020 W. 108th St.

Chicago IL 60655

312-535-2636

**Objective**: (Grades 4-8)

To review the ways in which fractions are made real in our world

To show the relationship of cross multiplication and equivalent fractions

To reinforce fraction skills

**Materials Needed**:

Measuring tape Construction paper

Pencil Equivalent fraction strips

Crayons Ditto of a boy and girl doll

**Recommended Strategy**:

This lesson has been designed to enrich the students understanding of fractions

after they have completed the study of fractions. Now we will attempt to show

that fractions indeed have a place in the real world.

The students have learned to add, subtract, multiply, and divide fractions.

They also know how to:

-change mixed numbers to improper fractions.

-reduce fractions to lowest terms.

-change fractions to a decimal; to a percent; to a ratio.

-find the LCM and GCF.

-solve or make equivalent fractions.

The students will have a discussion about why fractions are so important and

why students find understanding fractions so difficult. How can we make

fractions real to them? Following the discussion, the students will do various

activities: -Label a doll that represents the students measurements.

(students will add, subtract, multiply, divide, and reduce

fractions using their body measurements.)

-Use a calendar in order to do an activity that is a lead-in

to cross multiplication and proportions.

-Play an equivalent fraction game to reinforce problem

solving techniques.

**Performance Assessment**:

Students will set up a proportion in order to solve word problems.

**Multicultural Connections:**

The proportion property was recognized by the early Hindus as an arithmetic

rule. In the Seventh Century it was called the **rule of three** and was stated in

words in the style of the times. Merchants regarded the rule highly and used it

widely as a mechanical procedure without explanation. Prior to the Nineteenth

Century the ability to use the rule of three was a mark of mathematical

literacy. This explains cross multiplication and also how to find an unknown in

solving proportions. Ex. a/b = c/d therefore aKd = bKc

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