The numbers 1 – 9 may be used once and once only. How many different squares can you make altogether? Pebbles Age 7 to 11 Challenge Level: How can you arrange the 5 cubes so that you need the smallest number of Brush Loads of paint to cover them? Can you order the digits from to make a number which is divisible by 3 so when the last digit is removed it becomes a 2-figure number divisible by 2, and so on? Factors and Multiples KS2. Can you find the smallest number that lights up all four lights?

Use these four dominoes to make a square that has the same number of dots on each side. All the Digits Age 7 to 11 Challenge Level: How many possible necklaces can you find? To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice. Curious Number Age 7 to 11 Challenge Level: What could Lolla have paid for the balloon?

In this activity, the computer chooses a times table and shifts it. You are organising a school trip and you need to write a letter to parents to let them know about the day.

What can you say about these shapes? Highest and Lowest Age 7 to 11 Challenge Level: Can you work out the arrangement of the digits in the square so that the given products are correct? Imagine a pyramid which is built in square layers of small cubes.

What do you notice? What was the total and how could this be done? How many shapes can you build from three red and two green cubes? These eleven shapes each stand nrihc a different number.

# Area and Perimeter KS2 :

Factor Lines Age 7 to 14 Challenge Level: Choose a symbol to put into the number sentence. Try with different steps and see if you can predict what will happen. Investigate the sum of the numbers on the top and bottom faces of a line of three dice.

Can you arrange the sweets so that no sweets of the same colour are next to each other in any direction? Multiply Multiples 3 Age 7 to 11 Challenge Level: Register for our mailing list.

Register for our mailing list. Working Systematically at KS2. Tim had nine cards each with a different number from 1 to 9 on it.

The fourth article builds on the third by discussing what we mean by problem-solving skills and how NRICH can help children develop these skills. Zolving could explore this idea with other shapes too.

What happens when you enter different numbers? All the Digits Age 7 to 11 Challenge Level: Sweets in a Box Age 7 to 11 Challenge Level: Subtraction Surprise Age 7 to 14 Challenge Level: Flashing Lights Age 7 to 11 Challenge Level: Age 7 to 11 Challenge Level: Four of these clues are needed to find the chosen number on this grid and four are true but do nothing to help in finding the number.

## Problem-solving Skills

A game for two people, or play online. Norrie sees two lights flash at the same time, then one of them flashes every 4th second, and the other flashes every 5th second.

What Do You Need? Factor Lines Age 7 to 14 Challenge Level: Numerically Equal Age 7 to 11 Challenge Level: The idea is to go round the track in as few moves as possible, keeping to the rules.

Multiples Grid Age 7 to 11 Challenge Level: