Math Strategy: Getting to a Decade Number

What is the 'Getting to a Decade Number' math strategy?

Math Strategy: Getting to a Decade Number
Math Strand: Number sense and numeration

Location on the Continuum:

Overview:
Getting to a decade number and making jumps forwards and backwards of 10 is a strategy that builds upon the "Counting on from the larger number" strategy. Students will add up in chunks, first moving to the nearest decade number, and making larger jumps of 10 from there. For example, when solving 28 + ? = 50, the student would add 2 to get to 30, and then make two jumps of 10 to arrive at 50.

How this supports student learning:
As students encounter the challenge posed by adding or subtracting larger numbers, children will shift towards more efficient strategies. These strategies move along two general pathways, number-line related and splitting or decomposing strategies that lead to algorithms. Although there are two general pathways, number-line related strategies will only appear in classrooms that foster them.

Where to Next?
Games and activities that encourage Addition and Subtraction strategies involving jumps of 10 forward and backwards can be found in What to Look For by Alex Lawson on page 178.

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