Using Cuisenaire Rods to name a Fraction

The standard method of showing fractions with the Cuisenaire Rods is to place one rod over the other to compare their size. The rods can be shown vertically or horizontally (as shown below).

For Example:

Arrange your rods to represent 1/2 and 3/4 using the purple rod as the denominator. In order to represent 1/2 using the purple rod as the denominator we must first express the fraction in equivalent terms. Since 2 red rods in a train equals 4 cm. we must multiply the numerator and denominator by 2 red rods.

Take the numerator 1 * 2 red rods = 2

Take the denominator 2 * 2 red rods = 4

So representing 1/2 using the purple rod as the denominator equals 2/4 as shown below.

2/4 =

Now, in order to represent 3/4 using the purple rod as the denominator. Since 1 purple rod equals 4 cm. we must multiply the numerator and denominator times 1 purple rod.

Take the numerator 3 * 1 purple rod = 3

Take the denominator 4 * 1 purple rod = 4

So representing 3/4 using the purple rod as the denominator equals 3/4 as shown below.

3/4 =



Now it's your turn:

A. Arrange your rods to represent each of the following fractions using the dark green rod as the denominator.

For Example: 1/6 =

1.  1/2 =                   2. 2/3 =

3.  5/6 =                   4. 2/6 =



B. Arrange your rods to represent each of the following fractions using the brown rod as the denominator.

For Example: 4/8 =

5. 3/4 =                    6. 3/8 =

7. 2/8 =                    8. 5/8 =

C. Now for a real challenge! Let's say the orange and red rod are taped together as the unit. We'll call this color rorange. Represent each of the following fractions using the rorange rod as the denominator.

For Example: 7/12 =

9.  1/2 =                   10. 1/3 =

11. 1/4 =                   12. 5/6 =

Check your Answers.

© June 1997 Molly Silha