Rounding Whole Numbers

Rounding Whole Numbers

Grade Level: 3-4

Teacher Guidelines pages 1 ? 2 Instructional Pages pages 3 ? 4

Activity Page pages 5 - 6 Practice Page page 7 Homework Page page 8

Answer Key page 9 - 10

Classroom Procedure:

1. Display the jar of candy. Tell students the rounded off number of pieces in the jar to the nearest ten, saying there is about... pieces of candy in the jar. Ask students to then guess the exact number of pieces of candy, writing on a slip of paper and then turning it in to you.

2. Tell students that if they have the rounded off number: Do they think it was rounded to the nearest ten or one hundred?

3. Allow for responses and discussion.

4. Ask students why it is useful to round numbers.

5. Allow for responses and discussion.

6. Distribute the Rounding Whole Numbers content pages. Read and review the information with the students. Give additional examples to enhance student understanding.

7. Stress the rhyme to help students remember whether to add to or to keep the rounded digit the same.

8. Distribute the Activity page. Read and review the instructions with the students. You may wish to make additional pages for extra practice. Pair students. Distribute scissors.

9. Allow students sufficient time to complete the activity.

10.Once completed, students will exchange papers with another pair and will check each other's completed work.

11.Distribute the Practice page. Check and review the student's work.

12.Distribute the Homework page. The next day, check and review the student's work.

13.In closing, reveal the winner of the Candy Jar guess and share the candy with the class. Give extra to the winner.

14.Announce random numbers for students to round, checking for understanding.

Approximate Grade Level: 3 ? 4

Objectives:

The students will be able to round whole numbers to any place, and use rounding for word problems.

Common Core State Standards:

CCSS.Math.Content.3.NBT.A.1 CCSS.Math.Content.3.OA.D.8 CCSS.Math.Content.4.NBT.A.3 CCSS.Math.Content.4.OA.A.3

Class Sessions (45 minutes):

1 -2 class sessions

Teaching Materials/Worksheets:

Rounding Whole Numbers content page, Activity page, Practice page, Homework page

Student Supplies:

scissors, handouts

Prepare Ahead of Time:

Jar of candy between 100 and 200 pieces, know the exact count. Scissors for students. Copy handouts.

Options for Lesson:

Students may work alone for the activity, exchanging papers with one other student. Use the numbers students cut apart to practice rounding. Announce numbers students "write out" using the number slips, and then "write out" the rounded number you choose.

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Teacher Notes

The lesson is used to teach rounding of whole numbers. Students in younger grades need to know rounding to tens and hundreds, but older students should be able to round to any place value. All students should be familiar with place value up to the millions place. Students will have an easier time grasping this content with additional practice if necessary. _________________________________________________________________________________________

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Additional Resources: CONTENT: (and more) (Interactive) text_final.html (Interactive) (Interactive) (Interactive) . com/math/rounding/ (and Worksheets)

WORKSHEETS:

VIDEOS: (6 min) (4 min) (3 min-Song) (3 min-Song)

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Rouding Whole Numbers

When your friend tells you he scored 497 or 509 on a video game, in your mind you are probably thinking 500. You rounded both numbers to a more convenient number for you to use.

Rounding is changing the exact value of a number to a number that is more convenient or easier to use. Rounding a number may increase or decrease a number's value. If there are 37 people in the room and you say about 40, you rounded up, increasing the number's value. If there are 105 people in the room and you say 100, you rounded down, decreasing the number's value.

THOUSANDS ONES

4, 2 3 8, 5 6 7

Rounding is not difficult. You must know the place value of the digits in the numbers you will round. Look at the chart on the left and review the place value of each digit.

To round a whole number, you must first identify the place value to be rounded.

ONE MILLIONS HUNDRED THOUSANDS

TEN THOUSANDS ONE THOUSANDS

HUNDREDS TENS ONES

Here are two examples of rounding to the nearest thousand. Notice the difference.

PLACE VALUE

*Helpful rhyme to help you in rounding numbers:

12,367

Round to the nearest thousand.

12,367

Look to the right.

Is the number to the right 5 or above? Or is it 4 or lower? 3 is lower than 4 so the 2 in the thousands place stays the same. All the digits to the right of

the thousands place change to zeros:

The new rounded number is: 12,000

Five or above, give it a shove

(add one).

Four or below, you keep it low

(no change).

12,667

Round to the nearest thousand.

12,667

Look to the right.

Is the number to the right 5 or above? Or is it 4 or lower? 6 is higher than 5 so the 2 in the thousands place changes by adding one. All the digits

to the right of the thousands place still change to zeros:

The new rounded number is: 13,000

Did you notice the difference?

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Here are easy steps for rounding 25,189 to the nearest ten-thousands place: 1. Identify the ten-thousands place and underline it: 2 8 , 1 7 9 2. Look at the place value to the right* and circle it: 2 8 , 1 7 9 3. Is it five or above? YES. Add one to the digit in the ten-thousands place and change the other digits to the right to ZERO: 3 0 , 0 0 0 In summary, 28,179 rounded to the nearest ten-thousand is 30,000.

No matter how small or large the number may be, it can be rounded. Review some more examples, practice rounding numbers, and you will become an expert in rounding whole numbers of all sizes and digits.

Round 27 to the nearest ten: 2 7 3 0

Round 23 to the nearest tens: 2 3 2 0

Round 146 to the nearest hundreds: 1 4 6 1 0 0

Round 356 to the nearest hundreds: 3 5 6 4 0 0

Round 107,298 to the nearest thousands: 1 0 7 , 2 9 8

107,000

Round 255,908 to the nearest ten-thousands:

255,908

260,000

Round 3,267,705 to the nearest millions: 3 , 2 6 7 , 7 0 5

3,000,000

If there are 162 pieces of candy in the jar, about how many pieces to the nearest hundred are in the jar? How many pieces to the nearest ten are in the jar?

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