These squares have been made from Cuisenaire rods. Can you describe
the pattern? What would the next square look like?
Cut differently-sized square corners from a square piece of paper
to make boxes without lids. Do they all have the same volume?
Can you use this information to work out Charlie's house number?
One block is needed to make an up-and-down staircase, with one
step up and one step down.
$4$ blocks make an up-and-down staircase with $2$ steps up and
$2$ steps down.
How many blocks would be needed to build an up-and-down
staircase with $5$ steps up and $5$ steps down?
Explain how you would work out the number of blocks needed to
build a staircase with any number of steps.