Perimeter

This was a starter I used for a perimeter lesson. The children worked them out and then ranked them by difficulty. The children chose 3) and 4) to be the hardest. They explained their calculations and compared methods.

One child used 2) to work out 3). They said If 6 x 4 = 24 then I know 7x will be 4 greater because there will be 1cm extra on each side.