These activities lend themselves to systematic working in the sense that it helps to have an ordered approach. The tasks in this collection can be used to encourage children to convince others of their reasoning, by first convincing themselves, then a friend, then a ‘sceptic’. Table Patterns Go Wild! Make 37 Age 7 to 14 Challenge Level: Using the information given, can you replace the stars in the calculation with figures? The clever prison warder arranged them so there were 25 along each wall of the prison block.

Who said that adding couldn’t be fun? The planet of Vuvv has seven moons. Journeys in Numberland Age 7 to 11 Challenge Level: Can you make square numbers by adding two prime numbers together? Can you work out the table and the shift each time? Square Subtraction Age 7 to 11 Challenge Level:

## Problem-solving Skills

These lower primary tasks could all be tackled using a trial and improvement approach. How do the images help to explain this?

Factor Lines Age 7 to 14 Challenge Level: What Do You Need? What Do You Need?

Tasks for KS2 children which focus on working systematically. Scroll down to see our complete collection of KS2 problems that require children to work systematically, or explore the two sub-collections focusing on important aspects of systematic working. Tim had nine cards each with a different number from 1 to 9 on it.

Can you use the information to find out which cards I have used? What numbers could be inside the envelopes?

## The Puzzling Sweet Shop

On a digital clock showing 24 hour time, over a whole day, how many times pronlem a 5 appear? 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. Remainders Age 7 to 14 Challenge Level: Make 37 Age 7 to 14 Challenge Level: This feature is somewhat larger than our usual features, but that is because it is packed with resources to help you develop a problem-solving approach to the teaching and learning of mathematics.

The numbers 2 were used pdoblem generate it with just one number used twice.

# The Puzzling Sweet Shop :

How many shapes can you build from three red and two green cubes? The sum of the numbers inside it is written on each envelope. This big box multiplies y that goes inside it by the same number. He could then pay any sum of money from 1p to 15p without opening any bag. Look at different ways of dividing things. Journeys in Numberland Age 7 to 11 Challenge Level: Curious Number Age 7 to 11 Challenge Level: Choose two of the numbers to multiply or divide, then mark your answer on the number line.

# Problem Solving :

Can you find out enough to guarantee a win, no matter what the settings? Can you discover its value in each problem?

Maze Age 7 to 11 Challenge Level: This challenge is a game for two players. Who said that adding couldn’t be fun?

Three children are going to buy some plants for their birthdays. There is a clock-face nricj the numbers have become all mixed up. Three Neighbours Age 7 to 11 Challenge Level: Sweets in a Box Age 7 to 11 Challenge Level: Can you fill in this table square? Dice in a Corner Age 7 to 11 Challenge Level: This dice train has been made using specific rules.