Lesson Standard: 5.NF.2 Solve word problems involving addition and subtraction of fractions referring to the same whole, including cases with unlike
denominators, e.g., by using visual fraction models or equations to represent the problems. Use benchmark fractions and number sense of fractions to estimate
mentally and assess the reasonableness of answers.
Content Objective: Students will use benchmark fractions and number sense of fractions to estimate mentally and assess the reasonableness of answers.
Mathematical practice(s): 1 Make sense of problems and persevere, 4 Model with mathematics, 6 Attend to precision
Lesson Design
Engage (Launch)
4/8, 7/14, 6/12, 5/10
What do you notice
about these fractions?
What do you wonder
about these fractions?
How do you know it is
one half?
Give numerator
students respond with
denominator. (Students
can show on their
fingers) 2, 4, 5
numerators
Give denominator,
students respond with
numerator. (Students
can show on their
fingers) 12th , 20th , 100th
denominators
If the denominator is 7
what is the numerator?
What would be a way to
What will the teacher
be doing?
Teacher will place the
fractions on the board
and ask students to
discuss the questions
with their partner.
After questions ….
State: now we know
some benchmark
numbers. 0, ½, 1. (Draw
a number line on the
board and place the
benchmarks on the
number line) These
numbers help us when
we are discussing
fractions. Benchmarks
are numbers we know
for sure and can
compare fractions
against them.
What will the students
be doing?
What will the teacher
be listening for?
(Structured Student
Interaction)
(What do we expect
students to say?)
Students will discuss
their answer with their
partner. Partner A will
share first.
Equal to ½
Numerator
Denominator
Numerator is ½ of the
denominator
Probing Questions for Differentiation
Assessing Questions
(“stuck”)
Advancing Questions
(further learning)
Do you see any
relationship between
the numerator and
denominator?
Add fractions with the
same relationship to the
list.
Lesson Standard: 5.NF.2 Solve word problems involving addition and subtraction of fractions referring to the same whole, including cases with unlike
denominators, e.g., by using visual fraction models or equations to represent the problems. Use benchmark fractions and number sense of fractions to estimate
mentally and assess the reasonableness of answers.
Content Objective: Students will use benchmark fractions and number sense of fractions to estimate mentally and assess the reasonableness of answers.
Mathematical practice(s): 1 Make sense of problems and persevere, 4 Model with mathematics, 6 Attend to precision
write one whole as a
fraction? What is the
relationship between
the numerator and
denominator?
How many halves are
equal to zero? What is
the relationship
between the numerator
and denominator?
Activity or Task 1
Kimberly is riding her
bike to school. The
distance from her house
to school is 7/8 of a
mile. About how far is
Kimberly’s house from
the school? Show how
you know.
Teacher will place
problem on doc camera
and have students work
with a partner to discuss
the answer.
Students will work with
partner to answer the
problem. Students will
show on their
whiteboards how they
know their answer is
right. (Bs are writing)
Number lines
Use of benchmark
numbers
Can you relate it to a
benchmark number?
Activity or Task 2
Kimberly is now in
middle school. The
distance to her middle
school is 3/5 of a mile
more. About how far did
she ride altogether?
Teacher will place
problem on doc camera
and have students work
with a partner to discuss
the answer.
Students will work with
partner to answer the
problem. Students will
show on their
whiteboards how they
know their answer is
right. (As write)
Number lines
Use of benchmark
numbers
Can you relate it to a
benchmark number?
How do you know it isn’t
closer to 1/2?
Lesson Standard: 5.NF.2 Solve word problems involving addition and subtraction of fractions referring to the same whole, including cases with unlike
denominators, e.g., by using visual fraction models or equations to represent the problems. Use benchmark fractions and number sense of fractions to estimate
mentally and assess the reasonableness of answers.
Content Objective: Students will use benchmark fractions and number sense of fractions to estimate mentally and assess the reasonableness of answers.
Mathematical practice(s): 1 Make sense of problems and persevere, 4 Model with mathematics, 6 Attend to precision
Activity or Task 3
Kimberly will be riding
her bike to the store.
The distance from her
house to the end of the
street is 1/6 of a mile.
The distance from the
end of the street to the
store is 3/8 of a mile.
About how far is
Kimberly’s house from
the store?
Closure
Estimate the sum or
difference.
9/10 – 5/8
4 2/7 – 2 3/5
Teacher will place
problem on doc camera
and have students work
with a partner to discuss
the answer.
Students will work with
partner to answer the
problem. Students will
show on their
whiteboards how they
know their answer is
right. (As write)
Hand out the papers for
students complete
independently.
Students complete
handout independently.
Number lines
Use of benchmark
numbers
Can you relate it to a
benchmark number?
Lesson Standard: 5.NF.2 Solve word problems involving addition and subtraction of fractions referring to the same whole, including cases with unlike
denominators, e.g., by using visual fraction models or equations to represent the problems. Use benchmark fractions and number sense of fractions to estimate
mentally and assess the reasonableness of answers.
Content Objective: Students will use benchmark fractions and number sense of fractions to estimate mentally and assess the reasonableness of answers.
Mathematical practice(s): 1 Make sense of problems and persevere, 4 Model with mathematics, 6 Attend to precision
Kimberly is riding her bike to school. The distance from her house
to school is 7/8 of a mile. About how far is Kimberly’s house from
the school? Show how you know.
Now Kimberly is going to middle school. The distance to her middle
school is 3/5 of a mile more. About how far did she ride altogether?
Kimberly will be riding her bike to the store. The distance from her
house to the end of the street is 1/6 of a mile. The distance from
the end of the street to the store is 3/8 of a mile. About how far is
Kimberly’s house from the store?
Lesson Standard: 5.NF.2 Solve word problems involving addition and subtraction of fractions referring to the same whole, including cases with unlike
denominators, e.g., by using visual fraction models or equations to represent the problems. Use benchmark fractions and number sense of fractions to estimate
mentally and assess the reasonableness of answers.
Content Objective: Students will use benchmark fractions and number sense of fractions to estimate mentally and assess the reasonableness of answers.
Mathematical practice(s): 1 Make sense of problems and persevere, 4 Model with mathematics, 6 Attend to precision
1. Estimate the sum or difference using benchmarks. Show your thinking.
9
10
-
5
8
2. Estimate the sum or difference using benchmarks. Show your thinking.
2
3
7
5
4 -2
Lesson Standard: 5.NF.2 Solve word problems involving addition and subtraction of fractions referring to the same whole, including cases with unlike
denominators, e.g., by using visual fraction models or equations to represent the problems. Use benchmark fractions and number sense of fractions to estimate
mentally and assess the reasonableness of answers.
Content Objective: Students will use benchmark fractions and number sense of fractions to estimate mentally and assess the reasonableness of answers.
Mathematical practice(s): 1 Make sense of problems and persevere, 4 Model with mathematics, 6 Attend to precision