Mathematics 5 curriculum guide 2015 I table of contents acknowledgements

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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
Suggested Resource
• Resource Link: https://www.
k12pl.nl.ca/curr/k-6/math/
grade-5/links/unit 2
-enrichment activities
Performance
• 
Close Nice Numbers - Display a number with four decimal places, 
e.g., 3.0917. Starting with whole numbers, ask students, “Is it 
closer to 3 or 4?” Then go to the tenths: “Is it closer to 3.0 or 
3.1?” Repeat with hundredths and thousandths. At each answer, 
challenge students to defend their choices. (Walle & Lovin, 2006)
(5N2.1) 
• 
Ask students to create a number line using cash register tape and 
use it to place a given set of decimals. Ask them how they decided 
where to place the numbers on the number line.
(5N2.1)
Journal
• 
Jill needs 4.673 m of velvet ribbon and 5.076 m of silk ribbon for 
costumes for the school play. When she went to the website to 
order, she found that they only sell ribbon by the tenth of a metre.
Ask students how much of each she should order. They should 
explain their answer.
(5N2.1)
Math Focus 5
Chapter 2, Lesson 9: Rounding 
Decimals 
TR: pp. 54-56
SB: pp. 66-68

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52
MATHEMATICS 5 CURRICULUM GUIDE 2015
Specific Outcomes
ADDING AND SUBTRACTING DECIMALS
Suggestions for Teaching and Learning
Students will be expected to:
Number
5N2 Continued...
Achievement Indicator:
5N2.2 Determine the 
approximate solution to a given 
problem not requiring an exact 
answer.
Estimation is valuable because it helps predict answers and check 
calculations. Students also need to be aware that an exact answer is 
not always necessary. Estimating is producing an answer that is “good 
enough” for the situation. Some situations call for more careful estimates 
than others. When providing students with problems or questions, 
attempt to make the problems as relevant to the students as possible. 
Discuss situations where estimation is used in real life. Discuss with the 
class situations in which estimation would be appropriate and instances 
where it would not. Possible suggestions might include the number of 
people at a crowded restaurant, the amount of pizza required for a party, 
measuring medicine to give to a baby, or the number of socks in your 
drawer. Ask questions such as:
• Is it okay to make an estimate?
• What are the benefits of estimating?
• When might an estimate be the best way to solve a problem?
Students should work with a variety of problems which require 
determining an approximate solution such as:
A toy store has a sale. The store will pay the tax if your purchase totals 
$25 or more. Jessica buys a computer game for $14.95 and some batteries 
for $4.99. About how much more would she need to spend in order to 
avoid paying tax?
Students may chose the estimation strategy to use in finding approximate 
solutions to problems. They should realize that some strategies will give 
closer estimates than others. Student exploration will help refine their 
choices of estimation method depending on the situation and nature of 
the problem.

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