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MATHEMATICS 5 CURRICULUM GUIDE 2015
Specific Outcomes
DIVISION
Suggestions for Teaching and Learning
Students will be expected to:
Number
5N3 Apply mental math
strategies and number properties
by:
• skip counting from a known
fact
• using doubling or halving
• using patterns in the 9s facts
• using repeated doubling or
halving
in order to understand, apply and
recall basic multiplication facts to
9 x 9 and related division facts.
[C, CN, ME, PS, R, V]
Achievement Indicator:
By the end of Grade 5, students should:
• understand and apply strategies for multiplication and related division
facts to 9 × 9
• recall multiplication and related divison facts to 9 × 9
As with multiplication, students should be exposed to a variety of
strategies to determine division facts, but mastery of each strategy
should not be expected for all students.
In Grade 4, students explored the relationship between multiplication
and division. Arrays and sets of objects are important in helping
students review and solidify this understanding and the computational
procedures for multiplication and division. Coloured tiles are effective
when exploring arrays for this purpose.
Using coloured tiles on an interactive white board, have a class
discussion to create as many rectangles as possible which use 20 square
units. Relate each of the rectangles to multiplication facts, (1 x 20,
2 x 10 and 4 x 5). Next, split each rectangle into equal groups of
coloured tiles to review the corresponding division facts. (20 ÷ 1 = 20;
20 ÷ 20 = 1; 20 ÷ 2 = 10; 20 ÷ 10 = 2; 20 ÷ 4 = 5; 20 ÷ 5 = 4) This may
also be completed using Kidspiration® software.
Remind students how they have previously used counters to model
division and then relate it to multiplication. Previous work on facts up
to 9 × 9 will now be extended as students divide two-digit numbers
where the quotient can be greater than 9.
Skip counting
from a known fact can be used as a tool for division. If
the known fact is 40 ÷ 8 = 5, for example, students could use this fact
to determine 56 ÷ 8 by skip counting up 2 more groups of 8 to get from
40
48
56. This shows that 56 ÷ 8 = 5 groups plus 2 more
groups, so 7 groups in total. Therefore, 56 ÷ 8 = 7.
Skip counting from a known fact can also work by skipping backward.
If the known fact is 80 ÷ 8 = 10, for example, students could use this
fact to determine 72 ÷ 8 by skip counting down 1 more group of 8 to
get from 80
72. There is one less group of 8 so 72 ÷ 8 is one less
group of 8 than 80 ÷ 8. Therefore, 72 ÷ 8 = 9.
Another strategy that students could use to determine a quotient is
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