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UNIT FRACTIONS AS UNDERAPPRECIATED
SUPERHEROES
Vicki JacobsCotsen Foundation
Art of Teaching Conference 2017
University of MissouriSusan Empson
University of North Carolina at GreensboroNaomi JessupAmy Hewitt
University of Texas at AustinGladys KrauseD’Anna Pynes
Other Partners: SRI & Teachers Development Group(Joan Case!)
What role do unit fractions play in our instruction?
ØFractions children first learn1/2 1/4 1/3
ØFractions used for naming and notating fractions & defining fraction terms (numerator, denominator)
ØFractions used in the first few examples when operating on fractions (+ – ✕ ÷)
What role do unit fractions play in our instruction?
ØFractions first learned1/2 1/4 1/3
ØFractions used for naming and notating fractions & defining fraction terms (numerator, denominator)
ØFractions used in the first few examples when doing operating on fractions (+ – ✕ ÷)
Building understanding with unit fractions
ØHelp children build understanding of:• Fractions (1/2, 1/3, 1/4, …)• Fraction quantities (1/2 apple, 1/3 can of paint,…)
• Fraction relationships (1/2 vs. 1/4, 1/3 vs. 1/9,…)
ØHelp children operate on fractions with understanding
Why are unit fractions special?
Ø Unit fractions clarify the relationship to a “whole”• A whole can be decomposed into a group of same-sized
unit fractions• Same-sized unit fractions can be grouped to make a
whole
Ø Unit fractions are building blocks for other fractions
Ø Relationships between unit fractions are building blocks for understanding equivalence
Unit fractions clarify the relationship to a “whole”
1 sandwich can be decomposed into 3 one-third sandwiches
1 = 1/3 + 1/3 + 1/31 = 3 × 1/3
3 one-third sandwiches can be grouped to make 1 sandwich
1/3 + 1/3 + 1/3 = 13 × 1/3 = 1
Sandwich(a whole)
A whole is the same as a grouping of same-sized unit fractions
Maddy (grade 3) Noah has 4 sandwiches. He wants to give 1/3 of a sandwich to each of his friends. How many friends can he feed before he runs out of sandwiches?
Maddy (grade 3) Noah has 4 sandwiches. He wants to give 1/3 of a sandwich to each of this friends. How many friends can he feed before he runs out of sandwiches?
A whole is the same as a grouping of same-sized unit fractions
1/3 of a sandwich1/3 of a
sandwich
1/3 of a sandwich
Maddy (grade 3) There are 10 pizzas, and on each pizza is 1/4 cup of pineapple. How much pineapple will we need?
Maddy (grade 3) There are 10 pizzas, and on each pizza is 1/4 cup of pineapple. How much pineapple will we need?
A whole is the same as a grouping of same-sized unit fractions
Grouped together for 1 whole
A whole is the same as a grouping of same-sized unit fractions
Key strategy features
ØDoes the child represent each individual unit fraction?
ØDoes the child group unit fractions to make a whole?
Continuum of understanding
A chef is making 14 pizzas. Each pizza takes 1/6 of a pound of cheese. How much cheese wil l the chef need to make all of the pizzas?
Represents each unit fraction
Groups to a
whole
Does the child represent each individual unit fraction?
Does the child group unit fractions to make a whole?
Elsa
A chef is making 14 pizzas. Each pizza takes 1/6 of a pound of cheese. How much cheese wil l the chef need to make all of the pizzas?
Represents each unit fraction
Represents each unit fraction
Does notgroup to a whole
Groups to a
whole
Does the child represent each individual unit fraction?
Does the child group unit fractions to make a whole?
Elsa
A chef is making 14 pizzas. Each pizza takes 1/6 of a pound of cheese. How much cheese wil l the chef need to make all of the pizzas?
Represents each unit fraction
Represents each unit fraction
Does notgroup to a whole
Groups to a
whole
Does the child represent each individual unit fraction?
Does the child group unit fractions to make a whole?
ElsaPeter
A chef is making 14 pizzas. Each pizza takes 1/6 of a pound of cheese. How much cheese wil l the chef need to make all of the pizzas?
Represents each unit fraction
Represents each unit fraction
Does notrepresent
unit fractions
Does notgroup to a whole
Groups to a
whole
Groups to a
whole
Does the child represent each individual unit fraction?
Does the child group unit fractions to make a whole?
Peter Elsa
A chef is making 14 pizzas. Each pizza takes 1/6 of a pound of cheese. How much cheese wil l the chef need to make all of the pizzas?
Represents each unit fraction
Represents each unit fraction
Does notrepresent
unit fractions
Does notgroup
Groups to a
whole
Groups to a
whole
Does the child represent each individual unit fraction?
Does the child group unit fractions to make a whole?
ElsaPeter Karisma
A chef is making 14 pizzas. Each pizza takes 1/6 of a pound of cheese. How much cheese wil l the chef need to make all of the pizzas?
Represents each unit fraction
Represents each unit fraction
Does notrepresent
unit fractions
Does notgroup to a whole
Groups to a
whole
Groups to a
whole
Does the child represent each individual unit fraction?
Does the child group unit fractions to make a whole?
KarismaPeter Elsa
A chef is making 14 pizzas. Each pizza takes 1/6 of a pound of cheese. How much cheese wil l the chef need to make all of the pizzas?
Represents each unit fraction
Represents each unit fraction
Represents some unit fractions
Does notrepresent
unit fractions
Does notgroup to a whole
Groups to a
whole
Groups to a
whole
Groups to a
whole
Does the child represent each individual unit fraction?
Does the child group unit fractions to make a whole?
KarismaPeter Elsa
A chef is making 14 pizzas. Each pizza takes 1/6 of a pound of cheese. How much cheese wil l the chef need to make all of the pizzas?
Represents each unit fraction
Represents each unit fraction
Represents some unit fractions
Does notrepresent
unit fractions
Does notgroup to a whole
Groups to a
whole
Groups to a
whole
Groups to a
whole
Groups to multiple wholes
Does notrepresent
unit fractions
Does the child represent each individual unit fraction?
Does the child group unit fractions to make a whole?
KarismaPeter Elsa
A chef is making 14 pizzas. Each pizza takes 1/6 of a pound of cheese. How much cheese wil l the chef need to make all of the pizzas?
Represents each unit fraction
Represents each unit fraction
Represents some unit fractions
Does notrepresent
unit fractions
Does notgroup to a whole
Groups to a
whole
Groups to a
whole
Groups to a
whole
Groups to multiple wholes
Does notrepresent
unit fractions
Does the child represent each individual unit fraction?
Does the child group unit fractions to make a whole?
KarismaPeter Elsa
Jamal
Grace
Peyton
DestinyJustineJasper
Lili Logan
Why are unit fractions special?
Ø Unit fractions clarify the relationship to a “whole”• A whole can be decomposed into a group of same-sized
unit fractions• Same-sized unit fractions can be grouped to make a
whole
Ø Unit fractions are building blocks for other fractions
Ø Relationships between unit fractions are building blocks for understanding equivalence
Jayden (4th): If 6 kids were going to share 4 candy bars equally, how much candy bar could each kid get?
Why are unit fractions special?
Ø Unit fractions clarify the relationship to a “whole”• A whole can be decomposed into a group of same-sized
unit fractions• Same-sized unit fractions can be grouped to make a
whole
Ø Unit fractions are building blocks for other fractions
Ø Relationships between unit fractions are building blocks for understanding equivalence
Take Aways
Ø Unit fractions help build fraction understanding• not just “starter” fractions• building blocks for other fraction concepts (non-
unit fractions and equivalence)
Ø Key indicators of children’s understanding of the whole as the same as a group of same-sized unit fractions (continuum of understanding)
• Does the child represent each unit fraction?• Does the child group unit fractions to make a whole
More worksheets at www.education.com/worksheetsCopyright © 2010-2011 by Education.com
Math
Fractions Equal to A fraction has two parts, a numerator and a denominator.
When the numerator is the same as the denominator, the fraction is equal to 1.Color in the shapes whose fractions are equal to 1.
Fill in the missing value.
#11
2445
20020
99
4848
9090
56
34
416
620
42
55
7117
55
=
6 1
1
=
15=
109109
=
45
numerator
denominator
More worksheets at www.education.com/worksheetsCopyright © 2010-2011 by Education.com
Math
Fractions Equal to A fraction has two parts, a numerator and a denominator.
When the numerator is the same as the denominator, the fraction is equal to 1.Color in the shapes whose fractions are equal to 1.
Fill in the missing value.
#11
2445
20020
99
4848
9090
56
34
416
620
42
55
7117
55
=
6 1
1
=
15=
109109
=
45
numerator
denominator