The ideas in this lesson are taken from Multiplication Division 2 ebook. Only a few examples of each problem type are shown; you should make more problems of each kind for the student.

This lesson explains an alternative algorithm for multiplying a two- or three-digit number in columns that can be easier for some children to grasp than the common one.

Multiplying in columns - easy algorithm
Free lesson plan from HomeschoolMath.net

You can also do 5 × 34 vertically (in columns), using distributive property.

Multiply the ones first.

Then multiply the tens and place
the result underneath. Remember,
the 3 in 34 is signifying 30.

Then add.

34
× 5

20

34
× 5

20
150

34
× 5

20
+ 150

170

5 × 4 = 20

5 × 30 = 150

Multiply the ones.

Multiply the tens.

Add.

64
× 8

32

64
× 8

32
480

64
× 8

32
+ 480

512

1. Multiply.

53
× 2

61
× 5

63
× 5

35
× 6

17
× 5

99
× 5

47
× 8

35
× 8

72
× 5

77
× 7

46
× 6

88
× 7

2. Write a mathematical sentence(s) for the problems. Multiply using the principle above (distributive property).

a) All seven houses on the Cat Lane have seven cats living in them. How many legs do those cats have total?

d) Jane bought seven cards and seven chocolate boxes for her seven friends. The cards cost total $14, and the boxes cost total $35. How much was her total bill?
How much did one card cost?
One chocolate box?

If you have a 3-digit number, the process is similar: 3 × 184

Multiply the ones first.

Then multiply
the tens.

Then multiply
the hundreds.

Then add.

184
× 3

12

184
× 3

12
240

184
× 3

12
240
300

184
× 3

12
240
+ 300

552

3 × 4 = 12

3 × 80 = 240

3 × 100 = 300

Multiply ones:

tens:

hundreds:

Add.

326
× 3

18

326
× 3

18
60

326
× 3

18
60
900

326
× 3

18
60
+ 900

978

3. Multiply.

353
× 2

161
× 5

327
× 3

123
× 3

103
× 9

167
× 5

199
× 5

420
× 2

245
× 4

Can you figure out what was multiplied?


×			4

		2	0
+	1	6	0


×			7

		4	2
+	1	4	0


×			6

		5	4
	2	4	0
+	6	0	0

Multiply in columns - the standard algorithm

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Multiplying in columns - easy algorithm Free lesson plan from HomeschoolMath.net

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Multiplying in columns - easy algorithm
Free lesson plan from HomeschoolMath.net