'Jump Strategy' for mental calculation

Maths: In maths we have been building up our skills in number so that we add numbers in the tens and hundreds.  Today I had many light bulbs in the class who could add big numbers in their heads using the 'Jump Strategy'. To get to this stage, students have practised breaking numbers up (3460 = 3000 + 400 + 60), knowing place value and counting forwards and backwards in 2's, 5's, 10's. These skills have helped us grasp the mental strategy of jumping by parts of a number to solve a calculation.

Henry showing his mental calculation on the whiteboard. 

(photo by Siena Bunton)