Mathematics 5 curriculum guide 2015 I table of contents acknowledgements

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MATHEMATICS 5 CURRICULUM GUIDE 2015
46
ADDING AND SUBTRACTING DECIMALS
Unit Overview
Focus and Context
Outcomes Framework
In this unit, students will build on their understanding of addition 
and subtraction of whole numbers and extend to include decimals.
The importance of adding the same place values continues; i.e., adding 
tenths to tenths, hundredths to hundredths and so on. In exploring 
operations with decimals, estimation plays a large role. Estimation is 
used in everyday situations because it is sometimes more practical and 
efficient than the time required to find an exact value. Students will use 
front-end estimation, compensation, rounding and compatible numbers 
to estimate a sum or difference and to determine if solutions they 
compute are reasonable.
GCO
Develop number sense
SCO 5N2
Use estimation strategies, including:
• front-end estimation
• compensation
• compatible numbers
• rounding 
in problem-solving contexts.
SCO 5N11
Demonstrate an understanding of addition and subtraction 
of decimals (limited to thousandths).

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MATHEMATICS 5 CURRICULUM GUIDE 2015
ADDING AND SUBTRACTING DECIMALS
47
SCO Continuum
[C] 
Communication 
[PS] Problem Solving
[CN] Connections
[R] Reasoning
[ME] Mental Mathematics [T] Technology
and Estimation
[V] Visualization