Mathematics 5 curriculum guide 2015 I table of contents acknowledgements

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MATHEMATICS 5 CURRICULUM GUIDE 2015
Specific Outcomes
MULTIPLICATION
Suggestions for Teaching and Learning
Students will be expected to:
Number
5N3.1 Describe the mental 
mathematics strategy used to 
determine a given basic fact, such 
as: 
• skip count up by one or two
groups from a known fact
• skip count down by one or two
groups from a known fact
• doubling
• patterns when multiplying by 9
• repeated doubling
• repeated halving
5N3 Continued...
In Grade 4, students used these mental mathematics strategies to 
determine multiplication facts to 9 x 9. A review of the strategies will be 
important. Examples of each of these strategies follow:
• skip count up by one or two groups from a known fact; e.g., since
5 × 7 = 35, then 6 × 7 is equal to 35 + 7 (42) and 7 × 7 is equal to
35 + 7 + 7 (49)
• skip count down by one or two groups from a known fact; e.g., if 
8 × 8 = 64, then 7× 8 is equal to 64 – 8 (56) and 6 × 8 is equal to
64 – 8 – 8 (48)
• doubling; e.g., for 8 × 3 think 4 × 3 = 12, so 8 × 3 = 12 + 12 (24)
• patterns when multiplying by 9; the tens digit of the product is 
always one less that the other factor, the sum of the two digits in the 
product is always 9; e.g., for 7 x 9, think: 1 less than 7 is 6, 6 and 3 
make 9, so the answer is 63.
• repeated doubling; e.g., if 2 × 6 is equal to 12, then 4 × 6 is equal to 
24 and 8 × 6 is equal to 48.
• repeated halving; e.g., for 60 ÷ 4, think 60 ÷ 2 = 30 and 30÷ 2 = 15. 
Teachers could read aloud Gregory Tang’s
 The Best of Times 
and 
encourage students to try out the strategies Tang suggests for any fact 
families for which they did not have a rule or strategy. Students could 
add to or revise their own strategy book including creating a cover which 
illustrates one of the strategies contained inside.