estimating and finding the sum of two and three digits.

level 1

100

12+34=

46

200

  77

+52

______

139

300

estimate and sum.

381+512=

400+500=900

893

400

Estimate and sum.

3,382+5,587=

9,000

8,969

500

246+54+233+205=

738

level 2

100

Communitive (order) Property of Addition:

7+5=5+?

7 

so, 7+5=5+7

200

99+21=

120

300

estimate and sum.

705+222=

700+200=900

727

400

Estimate and sum.

5,302+4,591

10,000

9,893

500

602+125+231=

958

level 3

100

Identify (zero) Property of Addition: 

17+?=17

0

so, 17+0=17

200

327+63=

390

300

estimate and sum.

98+591=

100+600=

689

400

Estimate and sum.

3,555+462=

4,100

4,017

500

Third grade is reading a book that is 85 pages long. They read 35 pages yesterday and 24 pages today. How many pages did third grade read in all?

35 (yesterday) + 24 (today)

35 + 24 =

59

level 4

100

55+29=

84

200

834+276=

1,110

300

estimate and sum.

947+362=

900+400=

1,309

400

Estimate and sum.

2,736+6,274=

9,000

9,010

500

Jesus had 62 sheep. He gave his disciples 49 of them. How many sheep does Jesus have now? 

62 sheep in total(:

he gave 49 away. 

So, 62 - 49 = 13

level 5

100

Associative (grouping) Property:

4+(2+3)=4+?

5

so, 4+(2+3)=4+5

200

88+74=

162

300

estimate and sum.

488+460

500+500=1000

948

400

Estimate and sum.

8,424+589=

9,000

9,013

500

59+506+302+24=

891