## 'That Number Square!' printed from http://nrich.maths.org/

When you arrive in the classroom on Monday morning you discover all the numbers have fallen off the class number square and they are in a heap on the floor. All that is left on the wall is a blank grid!

There's five minutes to go before the lesson starts and you need the number square.

Can you find a quick way of putting the numbers back in their right places on the grid?

Where will you start?

Before you start think - does your class number square start with $0$ or $1$? Or a different number?

Some of your friends may want to have a go too.

What different ideas are there about how to put the number tiles back as quickly as possible?

Click here to see how Jonah started.

Let us know what you think is a 'smart' way of putting the number square back together.

How quickly can you achieve this using your 'smart' strategy?