Visualising and representing

problem
Counters

Age

7 to 11

Challenge level

Hover your mouse over the counters to see which ones will be removed. Click to remove them. The winner is the last one to remove a counter. How you can make sure you win?
problem
Cuboid-in-a-box

Age

7 to 11

Challenge level

What is the smallest cuboid that you can put in this box so that you cannot fit another that's the same into it?
problem
Peg rotation

Age

7 to 11

Challenge level

Can you work out what kind of rotation produced this pattern of pegs in our pegboard?
problem
Cube drilling

Age

7 to 11

Challenge level

Imagine a 4 by 4 by 4 cube. If you and a friend drill holes in some of the small cubes in the ways described, how many will not have holes drilled through them?
problem
More pebbles

Age

7 to 11

Challenge level

Have a go at this 3D extension to the Pebbles problem.
problem
Square subtraction

Age

7 to 11

Challenge level

Look at what happens when you take a number, square it and subtract your answer. What kind of number do you get? Can you prove it?
problem
Subtraction surprise

Age

7 to 14

Challenge level

Try out these calculations. Are you surprised by the results?
problem
Your number is...

Age

7 to 14

Challenge level

Think of a number and follow the machine's instructions... I know what your number is! Can you explain how I know?
problem
The Number Jumbler

Age

7 to 14

Challenge level

The Number Jumbler can always work out your chosen symbol. Can you work out how?
problem
Number lines in disguise

Age

7 to 14

Challenge level

Some of the numbers have fallen off Becky's number line. Can you figure out what they were?