Mathematics
Grade 3
Rounding and Front-End Estimation
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Dear Parent or Guardian:
Your child is currently learning to estimate sums and differences
using rounding and front-end estimation. Here is your chance to
help your child practice this important skill.
In this PAL Packet you will find a short activity for you and your
child to do. Please do the activity and The Back Page this evening.
Then sign your name on The Back Page and have your child return it
tomorrow.
Remember, parents are a child’s first teacher. Thank you for your
time and energy in making learning fun and exciting for your child.
Sincerely,
_________________________
Your child’s teacher
Grade 3 – Rounding and Front-End Estimation
© 2004 Evans Newton Incorporated
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ESTIMATING SUMS AND DIFFERENCES
Parent Pointer —
Estimating involves calculating an amount that is not exact but is close
to the exact amount. You may estimate the number of donuts to buy or
the amount of gas needed for a trip. Estimating numbers helps your
child know more about number sense and allows him or her to use
numbers that are easier to work with.
Math in the Home, on the Go, and for the Fun of It —
DIRECTIONS: Read through and discuss the steps involved in
estimating on the How Do We Estimate? reference sheet with your
parent or guardian. Then, work with your parent or guardian to create
and solve some estimation problems on the Estimation Problems activity
pages.
Talk about It —
After you have finished the activity, turn to The Back Page to show
what you know.
Now go have some fun with the activity! (
Grade 3 – Rounding and Front-End Estimation
© 2004 Evans Newton Incorporated
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How Do We Estimate?
We can estimate by ROUNDING to the nearest ten.
Using a number line can help us with rounding.
60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80
30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
78
+ 42
Find these
numbers on the
number lines
above. Which
“ten” are they
closest to?
80
+ 40
120
We can also estimate by ROUNDING to the nearest
hundred. Use the number lines to help you estimate the
numbers in the problem below.
800
810
820
830
840
850
860
870
880
890
900
300
310
320
330
340
350
360
370
380
390
400
Find these
numbers on the
number lines
above. Which
“hundred” are
they closest to?
Grade 3 – Rounding and Front-End Estimation
890
+ 312
© 2004 Evans Newton Incorporated
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How Do We Estimate?
(continued)
We can estimate by FRONT-END estimation.
Using front-end
estimation, use
the first number
without worrying
about what it is
closest to.
76
+ 43
70
+ 40
110
We can use FRONT-END estimation with different
numbers of digits. Choose the number with the least
digits, 56. Then keep any digits to the left of the tens
place in the other numbers.
Using front-end
estimation, use
the first number
without worrying
about what it is
closest to.
183
- 56
180
- 50
130
Use FRONT-END estimation to estimate the answer in
the problem below.
Using front-end
estimation, use
the first number
without worrying
about what it is
closest to.
Grade 3 – Rounding and Front-End Estimation
2,691
+ 129
© 2004 Evans Newton Incorporated
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Estimation Problems
Directions: Cut out the numbers from the Cutout Numbers page. Place
the numbers in a bag or bowl. You and your parent or guardian will take
turns removing two numbers. Flip a coin to decide if you will write an
addition (+) problem (heads) or a subtraction (−) problem (tails). Then
take turns writing a problem. The person not writing the problem will
flip a coin to determine if the answer will be estimated by rounding
(heads) or by front-end estimation (tails). Use the graphics on the left
to help you write a problem or use your own ideas!
• Look at the example below to help in getting started:
Since your parent or guardian flipped a coin that landed on heads, he
or she wrote an addition problem. The numbers pulled from the bag
were 33 and 19.
Problem:
There were 33 people in the theater and 19 more
waiting in line. What is the estimated total number
of people who will see the movie?
Then you flipped a coin and it landed on heads, so you estimate the
answer using rounding. Write the numbers and their estimates, and
then solve the problem:
33
30
+ 19
+ 20
50
• Reread the directions at the top of this page and turn to the
next page to get started! You may draw number lines on the
reverse side of the page to help with estimating.
Grade 3 – Rounding and Front-End Estimation
© 2004 Evans Newton Incorporated
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Estimation Problems
(continued)
Grade 3 – Rounding and Front-End Estimation
© 2004 Evans Newton Incorporated
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Cutout Numbers
9
19
47
33
53
116
91
189
79
290
388
472
Grade 3 – Rounding and Front-End Estimation
© 2004 Evans Newton Incorporated
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The Back Page
Talk About It
Parent —
Ask your child the following questions:
9Why do we use rounding and front-end estimation to
solve addition and subtraction problems?
9How do we round numbers to the nearest ten?
9What do we do if we are using front-end estimation
and the number of digits in the numbers is different?
Student —
Answer the above questions in complete sentences on the
reverse side of this page.
OR
Do one of the following activities on the reverse side of
this page:
9Look in the newspaper to find sections where numbers
are used. Cut these numbers out and glue them to the
reverse side of this page. Use these numbers to
write some addition and subtraction problems. Ask
your parent or guardian to estimate the numbers, and
then solve the problem.
9Have your parent or guardian draw three pictures.
Write an addition or subtraction problem for each and
use estimation to solve.
__________________________ _________________________
Student’s Name
Parent or Guardian’s Signature
Grade 3 – Rounding and Front-End Estimation
© 2004 Evans Newton Incorporated
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