Unit 2: Multiplication
Session 3: Finding Products Less Than 100
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Learning Objectives:
a. Use rectangular arrays to find products less than 100;
b. Use grouping of 10 to find the products of two-digit and one-digit numbers;
c. Use multiplication to derive the products of two-digit and one-digit numbers.
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Learning Content:
Vocabulary：
Key Words (Contextual Story):
tiler
Key Words (Mathematical Terminology)
arrange, factor, regroup
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Lesson Content 1
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Q: How many rows of tiles are there?
There are three rows of tiles.
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Q: How many columns of tiles are there?
There are two columns of tiles.
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Key Questions: What multiplication shows 3 rows and 2 columns?
3 x 2 shows 3 rows and 2 columns.
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3 and 2 are called factors, and 6 is called product.
- Which multiplication sentence shows 4 rows and 9 columns? (4×9)
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What is the product of four and nine?
The product of four and nine is thirty-six.
Lesson Content 2 – Thinking Process
How do we multiply 4 and 36?
First, line up the digits (we put 36 on the top, and put 4 under 36.)
Second, we look at the ones place. 4 times 6 equals 24. Because 24 is greater than 10, we can regroup 20 ones as 2 tens and move them to the tens place. So 4 is left in the ones place.
Third, we look at the tens place. We need to multiply 4 and 3 tens. 4 times 3 equals 12. 12+2=14. Because 14 is greater than 10, we can regroup 10 tens as 1 hundred and move it to the hundreds place. So 4 is left in the tens place.
Then, we look at the hundreds place. 1 is in the hundreds place.
Finally, 1 hundred, 4 tens and 4 ones is 144. So 4 times 36 equals 144.
–===================Lesson 2: PracticeQ: What’s the product of each multiplication?
Answers: 42/96/252/108===================Lesson 3: Workout (You Try)