Try out these calculations. Are you surprised by the results?
Watch our videos of multiplication methods that you may not have met before. Can you make sense of them?
Can you find rectangles where the value of the area is the same as the value of the perimeter?
A country has decided to have just two different coins. Which totals can be made? Is there a largest total that cannot be made? How do you know?
Invent a scoring system for a 'guess the weight' competition.
Think of a number and follow my instructions. Tell me your answer, and I'll tell you what you started with! Can you explain how I know?
Imagine we have four bags containing a large number of 1s, 4s, 7s and 10s. What numbers can we make?
Which of these pocket money systems would you rather have?
Charlie and Abi put a counter on 42. They wondered if they could visit all the other numbers on their 1-100 board, moving the counter using just these two operations: ×2 and -5. What do you think?
There are lots of ideas to explore in these sequences of ordered fractions.
Can you work out what step size to take to ensure you visit all the dots on the circle?
Can you make a right-angled triangle on this peg-board by joining up three points round the edge?
Which countries have the most naturally athletic populations?
Alison and Charlie are playing a game. Charlie wants to go first so Alison lets him. Was that such a good idea?
How well can you estimate 10 seconds? Investigate with our timing tool.
Play around with sets of five numbers and see what you can discover about different types of average...
Use properties of numbers to work out whether you can satisfy all these statements at the same time.
Here is a machine with four coloured lights. Can you develop a strategy to work out the rules controlling each light?
Sequences of multiples keep cropping up...
What's the largest volume of box you can make from a square of paper?
