Mathematics 5 curriculum guide 2015 I table of contents acknowledgements

5N2 Continued...
Achievement Indicators:
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MATHEMATICS 5 CURRICULUM GUIDE 2015
Suggested Assessment Strategies
Resources/Notes
ADDING AND SUBTRACTING DECIMALS
General Outcome: Develop Number Sense
Authorized Resource
Paper and Pencil
• Students could estimate to determine which combination of 
animals can safely cross bridges with the given load limits.
(a) Bridge A: load limit of 800 kg
(b) Bridge B: load limit of 1 100 kg
(5N2.3, 5N2.4)
Interview
• Terry-Lynn had $257. She spent $173.75. She estimates that she has less 
than $100 dollars left. Ask students if her estimate is reasonable. Explain.
(5N2.3)
Performance
• Place students in groups of two or three. Provide each group with 
a weekly retail flyer. Ask each group to use front-end estimation 
to purchase items from the flyer to get a total as close as possible, 
without going over, a given amount. Have groups share their 
strategies with the class. 
(5N2.3, 5N2.4)
Note
Math Focus 5
does not reference 
the estimation strategies of front-
end estimation, compensation and 
compatible numbers in solving 
problems. Further development of 
these strategies should use material 
from this guide.
Math Focus 5
Chapter 3: Lesson 1: Estimating 
Whole-Number Sums and 
Differences
TR: pp. 13-17
SB: pp. 82-85
Chapter 3: Lesson 2: 
Communicating About Estimating 
and Calculating
TR: pp. 18-21
SB: pp. 86-87
• Ask students to estimate the solution to each of the following 
problems:
(i) Mount Everest is 8.850 km high. Mount Logan is 5.959 km
high. What is their height difference?
(ii) Jenny and her 11 friends go out to eat at a restaurant. Each
meal costs $9.97 including GST and the tip. Will $100 cover
the cost of the meals?
(iii) During one summer, Marcie travels 7 185 km and Jimmy
travels 4 205 km. Estimate how much farther Marcie travels
than Jimmy during the summer. Explain your thinking. Do
you think your estimate is more or less than the calculated
answer? Explain your reasoning.
(5N2.2, 5N2.3, 5N2.4)
Bear 
186 kg 
Moose 
473 kg 
Cow 
417 kg 
Tiger 
223 kg 

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