Pupils may make errors when crossing the 100s boundary, either when adding or subtracting.
Emphasise that ten 10s are equal to 100. When using base ten blocks, pupils should be encouraged to change ten 10s into one hundred.
Multiple - The result of multiplying a number by another whole number.
100s boundary - The point at which the numbers change into 100s numbers, or from one set of hundreds to another.
What number is represented by the base ten blocks?
What number is represented by the arrow?
