Fractions, Decimals and
Percents Mini-course
Session Four
Objectives
• To use Cuisenaire Rods as a manipulative
for illustrating fraction concepts.
• To explore the fraction concepts of
equivalence, unit and non – unit fractions,
and reciprocals.
• To introduce the NCTM Communication
Standard.
NCTM Communication Standard
Instructional programs P-12 should enable all
participants to:
• Communicate their mathematical thinking
coherently and clearly to peers, teachers,
and others.
• Analyze and evaluate the mathematical
thinking and strategies of others.
Homework Discussion
• Each group should write a solution to one
problem on a flip chart.
• Volunteers can share the solutions with
the class.
Cuisenaire Rods
• Cuisenaire rods are another manipulative
we can use to develop understanding of
fractions.
• With a partner figure out one way you
might use Cuisenaire rods to represent
fractions. Share your ideas with the group.
Measuring Map Activity
• The relative rods build a stair step pattern.
• Use the Cuisenaire rods to measure relative
distances.
• If brown rods are placed along the entire route,
then the police station is 1/3 of the way from my
house to my school and the Burger Barn is 2/3
of the way from my house to my school. Write
these fractions next to their place names on your
list.
• Work with a partner to complete BLM 21 & 22
BLM 22
Defining Fractional Rod
Relationships
Work with a partner and find as many
fractional relationships as possible using
the Cuisenaire rods.
e.g. red is ½ of purple.
A) _________ is ½ of__________
B) _________ is 1/3 of _________
C) _________ is ¼ of___________
Fractional Rod Relationships
• When the smaller lengths fit evenly into
the larger lengths, these are considered
unit fractions.
• Now consider:
Light green is________ of brown
Find rods that divide brown and green
evenly to solve this relationship.
• Purple is __________ of orange.
Can you think of two different ways
(equivalent fractions) to express the
purple vs orange?
Challenge your partner
• Have one partner to take out any two
different rods.
– Have other partner compare rods and
describe what fraction the smaller rod is
of the larger one.
• Trade roles a few times back & forth.
BLM 23
Volunteers to
demonstrate solutions?
A new challenge
• What happens when a LARGER rod is
compared to a SMALLER rod?
• Recall that yellow is ½ of orange.
=> Orange is ________ of yellow.
• Recall purple is 2/5 of orange.
=> Orange is _______ of purple.
Challenge your partner, AGAIN
• Have one partner to take out any two
different rods.
– Have other partner compare rods and
describe what fraction the smaller rod is
of the larger one, AND what fraction the
larger rod is to the smaller one!
• Trade roles a few times back & forth.
This activity demonstrates the term Reciprocal.
Reflection
• Reflect on the experience of learning or relearning fractions using manipulatives.
• Discuss with a partner how your children
might benefit by learning fractions through
manipulatives and group work.
• Share your reflection with the class.
• Bringing it Home Activity 4 & Fraction III