Watch the Clock Age 7 to 11 Challenge Level: Sweets in a Box Age 7 to 11 Challenge Level: How many shapes can you build from three red and two green cubes? Becoming confident and competent as a problem solver is a complex process that requires a range of skills and experience. Each light in this interactivity turns on according to a rule. Tom and Ben visited Numberland. What Is the Time?

Multiply Multiples 1 Age 7 to 11 Challenge Level: Nearly all of us have made table patterns on hundred squares, that is 10 by 10 grids. Remainders Age 7 to 14 Challenge Level: What happens when you enter different numbers? We start with one yellow cube and build around it to make a 3x3x3 cube with red cubes. Can you make square numbers by adding two prime numbers together?

Can you put these mixed-up times in order? Choose four different digits from and put one in each box so that the resulting four two-digit numbers add to a total of At what time, to the nearest second, does problek happen?

Explore Alex’s number plumber. Prison Cells Age 7 to 11 Challenge Level: Factor Lines Age 7 to 14 Challenge Level: Pick any ten numbers from the bags above so that their total is Holes Age 5 to 11 Challenge Level: Can you find out where all the numbers have got to from these ten statements? By explicitly drawing children’s attention to these four stages, and by spending solvihg on them in turn, we can help children become more confident problem solvers.

How many Zios and how many Zepts were there? Find the chain which contains the smallest possible numbers. This ks22 has ink on each face which leaves marks on paper as it is rolled.

Age 5 to 7 Trial and Improvement at KS1 These lower primary tasks could all be tackled using a trial and improvement approach. Half Time Age 5 to 11 Challenge Level: During the third hour after midnight the hands on a clock point in the same direction so one hand is over the top of the other.

Can you find the smallest number that lights up all four lights? How many different trains can you make? All the Digits Age 7 to 11 Challenge Level: These upper primary tasks could all be tackled using a trial and improvement approach. Age 7 to 11 Conjecturing and Generalising at KS2 The tasks in this collection encourage upper primary children to conjecture and generalise.

## Addition and Subtraction KS2

Ram divided peoblem pennies among four small bags. Imagine a pyramid which is built in square layers of small cubes. The Zios have 3 legs and the Zepts have 7 legs.

Two Clocks Age 7 to 11 Challenge Level: What is the largest ‘ribbon square’ you can make?

# Addition and Subtraction KS2 :

Can you arrange the sweets atcivities that no sweets of the same colour are next to each other in any direction? This task combines spatial awareness with addition and multiplication. Three Neighbours Age 7 to 11 Challenge Level: Four bags contain a large number of 1s, 3s, 5s and 7s.

This big box multiplies anything that goes inside it by the same number. Use the information to work out what time the real time they arrived at the airport. Using the information given, can you replace the stars in the calculation with figures?

## Working Systematically at KS2

This challenge encourages you to explore dividing a three-digit number by a single-digit number. If we number the cubes from the top, starting with 1, can you picture which cubes are directly below this first cube?

These activities focus on finding all possible solutions so working in a systematic way will ensure none are left out.

Put operations signs between the numbers 3 4 5 6 to make the highest possible number and lowest possible number.