1. Warm Up
Heather plans to mow lawns to earn extra money. She will charge $25.00 for each lawn she mows. She estimates she will be able to save all the money except for $3.00 per lawn. How many lawns will she need to mow in order to save $200?

2. Use Benchmarks to Round Decimals Alignment Lesson

3. Decimal Benchmarks Study the decimals
Decimals Near or Equal to 0
0.012
0.17
0.23
0.009
0.1
0.20
0.0
Study the decimals
shown and see what they have in common
Generate rules for determining if decimals are close or equal to 0
Find Day 26 “Decimal Benchmarks”
Record rules in the first column of the chart.

4. Decimal Benchmarks Study the decimals
Decimals Near or Equal to 0
0.012
0.17
0.23
0.009
0.1
0.20
0.0
Decimals near or equal to zero have a 0 in the ones place.
Decimals near or equal to zero have a 0, 1 or 2 in the tenths place.
Decimals equal to 0 have a 0 in the ones place and a 0 in the tenths place (and sometimes zeros in the hundredths and thousandths places).
Decimals near or equal to zero that have a 2 in the tenths place have a digit under 5 in the hundredths place.
Study the decimals
shown and see what they have in common
Generate rules for determining if decimals are close or equal to 0
Find Day 24 “Decimal Benchmarks”
Record rules in the first column of the chart.

5. Decimal Benchmarks
Decimals Near or Equal to 0
Decimals Near or Equal to
0.012
0.17
0.23
0.009
0.1
0.20
0.0
0.62
0.490
0.500
0.4
0.53
0.617
Study the decimals in the new column and see what they have in common
Generate rules for determining if decimals are close or equal to 0
Record rules in the first column of the chart.

6. Decimal Benchmarks
Decimals Near or Equal to 0
Decimals Near or Equal to
0.012
0.17
0.23
0.009
0.1
0.20
0.0
Decimals near or equal to zero have a 0 in the ones place.
Decimals near or equal to zero have a 0, 1 or 2 in the tenths place.
Decimals equal to 0 have a 0 in the ones place and a 0 in the tenths place (and sometimes zeros in the hundredths and thousandths places).
Decimals near or equal to zero that have a 2 in the tenths place have a digit under 5 in the hundredths place.
0.62
0.490
0.500
0.4
0.53
0.617
Decimals near or equal to 0.5 have a 0 in the ones place.
Decimals near or equal to 0.5 have a 4, 5, 6 or 7 in the tenths place.
Decimals equal to 0.5 have a 0 in the ones place, a 5 in the tenths place (and sometimes zeros in the hundredths and thousandths places).
Decimals near or equal to 0.5 that have a 7 in the tenths place, have a digit under 5 in the hundredths place.
Study the decimals in the new column and see what they have in common
Generate rules for determining if decimals are close or equal to 0
Record rules in the first column of the chart.

7. Decimal Benchmarks
Decimals Near or Equal to 0
Decimals Near or Equal to
Decimals Near or Equal to
0.012
0.17
0.23
0.009
0.1
0.20
0.0
0.62
0.490
0.500
0.4
0.53
0.617
1.12
0.9
0.893
0.901
1.24 1
Study the decimals in the new column and see what they have in common
Generate rules for determining if decimals are close or equal to 0
Record rules in the first column of the chart.

8. Decimals Near or Equal to 0
0.012
0.17
0.23
0.009
0.1
0.20
0.0
Decimals near or equal to zero have a 0 in the ones place.
Decimals near or equal to zero have a 0, 1 or 2 in the tenths place.
Decimals equal to 0 have a 0 in the ones place and a 0 in the tenths place (and sometimes zeros in the hundredths and thousandths places).
Decimals near or equal to zero that have a 2 in the tenths place have a digit under 5 in the hundredths place.
0.62
0.490
0.500
0.4
0.53
0.617
Decimals near or equal to 0.5 have a 0 in the ones place.
Decimals near or equal to 0.5 have a 4, 5, 6 or 7 in the tenths place.
Decimals equal to 0.5 have a 0 in the ones place, a 5 in the tenths place (and sometimes zeros in the hundredths and thousandths places).
Decimals near or equal to 0.5 that have a 7 in the tenths place, have a digit under 5 in the hundredths place.
1.12
0.9
0.893
0.901
1.24 1
Decimals near or equal to 1.0 have a 1 in the ones place and a 0, 1 or 2 in the tenths place.
Decimals near or equal to 1.0 with a 2 in the tenths place, have a digit smaller than 5 in the hundredths place.
Decimals near or equal to 1.0 have a 0 in the ones place and an 8 or 9 in the tenths place.
Decimals equal to 1.0 have a 1 in the ones place and a zero in the tenths place (and sometimes zeros in the hundredths and thousandths places).
Decimal Benchmarks
Study the decimals in the new column and see what they have in common
Generate rules for determining if decimals are close or equal to 0
Record rules in the first column of the chart.

9. Decimal Benchmarks
Decimals Near or Equal to 0
Decimals Near or Equal to 0.5
Decimals Near or Equal to 1.0
Decimals Near or Equal to 1.5
0.012
0.17
0.23
0.009
0.1
0.20
0.0
0.62
0.490
0.500
0.4
0.53
0.617
1.12
0.9
0.893
0.901
1.24 1
1.470
1.50
1.600
1.43
1.710
1.39
Study the decimals in the new column and see what they have in common
Generate rules for determining if decimals are close or equal to 0
Record rules in the first column of the chart.

10. Decimal Benchmarks Decimals Near or Equal to 0
0.012
0.17
0.23
0.009
0.1
0.20
0.0
Decimals near or equal to zero have a 0 in the ones place.
Decimals near or equal to zero have a 0, 1 or 2 in the tenths place.
Decimals equal to 0 have a 0 in the ones place and a 0 in the tenths place (and sometimes zeros in the hundredths and thousandths places).
Decimals near or equal to zero that have a 2 in the tenths place have a digit under 5 in the hundredths place.
0.62
0.490
0.500
0.4
0.53
0.617
Decimals near or equal to 0.5 have a 0 in the ones place.
Decimals near or equal to 0.5 have a 4, 5, 6 or 7 in the tenths place.
Decimals equal to 0.5 have a 0 in the ones place, a 5 in the tenths place (and sometimes zeros in the hundredths and thousandths places).
Decimals near or equal to 0.5 that have a 7 in the tenths place, have a digit under 5 in the hundredths place.
1.12
0.9
0.893
0.901
1.24 1
Decimals near or equal to 1.0 have a 1 in the ones place and a 0, 1 or 2 in the tenths place.
Decimals near or equal to 1.0 with a 2 in the tenths place, have a digit smaller than 5 in the hundredths place.
Decimals near or equal to 1.0 have a 0 in the ones place and an 8 or 9 in the tenths place.
Decimals equal to 1.0 have a 1 in the ones place and a zero in the tenths place (and sometimes zeros in the hundredths and thousandths places).
1.470
1.50
1.600
1.43
1.710
1.39
Decimals near or equal to 1.5 have a 1 in the ones place and a 3, 4, 5, 6 or 7 in the tenths place.
Decimals near or equal to 1.5 with a 7 in the tenths place, have a digit smaller than 5 in the hundredths place.

11. Decimal Benchmarks
Decimals Near or Equal to 0
Decimals Near or Equal to 0.5
Decimals Near or Equal to 1.0
Decimals Near or Equal to 1.5
Decimals Much Greater Than 1.5
0.012
0.17
0.23
0.009
0.1
0.20
0.0
0.62
0.490
0.500
0.4
0.53
0.617
1.12
0.9
0.893
0.901
1.24 1
1.470
1.50
1.600
1.43
1.710
1.39
3.01
14.2
Study the decimals in the new column and see what they have in common
Generate rules for determining if decimals are close or equal to 0
Record rules in the first column of the chart.

12. Decimal Benchmarks Decimals Near or Equal to 0
Decimals Much Greater Than 1.5
0.012
0.17
0.23
0.009
0.1
0.20
0.0
Decimals near or equal to zero have a 0 in the ones place.
Decimals near or equal to zero have a 0, 1 or 2 in the tenths place.
Decimals equal to 0 have a 0 in the ones place and a 0 in the tenths place (and sometimes zeros in the hundredths and thousandths places).
Decimals near or equal to zero that have a 2 in the tenths place have a digit under 5 in the hundredths place.
0.62
0.490
0.500
0.4
0.53
0.617
Decimals near or equal to 0.5 have a 0 in the ones place.
Decimals near or equal to 0.5 have a 4, 5, 6 or 7 in the tenths place.
Decimals equal to 0.5 have a 0 in the ones place, a 5 in the tenths place (and sometimes zeros in the hundredths and thousandths places).
Decimals near or equal to 0.5 that have a 7 in the tenths place, have a digit under 5 in the hundredths place.
1.12
0.9
0.893
0.901
1.24 1
Decimals near or equal to 1.0 have a 1 in the ones place and a 0, 1 or 2 in the tenths place.
Decimals near or equal to 1.0 with a 2 in the tenths place, have a digit smaller than 5 in the hundredths place.
Decimals near or equal to 1.0 have a 0 in the ones place and an 8 or 9 in the tenths place.
Decimals equal to 1.0 have a 1 in the ones place and a zero in the tenths place (and sometimes zeros in the hundredths and thousandths places).
1.470
1.50
1.600
1.43
1.710
1.39
Decimals near or equal to 1.5 have a 1 in the ones place and a 3, 4, 5, 6 or 7 in the tenths place.
Decimals near or equal to 1.5 with a 7 in the tenths place, have a digit smaller than 5 in the hundredths place.
3.01
14.2
22.4
15.0
99.8
37.006
Decimals much greater than 1.5, have whole numbers that are much greater than 1.

13. In Groups of 3 to 4…
Need: Set of Decimal Cards (in teacher’s notebook) AND large sheet of construction paper
Divide your sheet into 5 columns
Copy the headings from the chart you’ve just used.
Work together to place the cards in the correct column, gluing them down once the group has reached consensus.
Decimals Near or Equal to
Decimals Near or Equal to
Decimals Near or Equal to
Decimals Near or Equal to
Decimals Much Greater Than 1.5

14. Day 26 “Use Benchmarks to Round Decimals Journal Prompt”
Homework
Day 26 “Use Benchmarks to Round Decimals Journal Prompt”