How many centimetres of rope will I need to make another mat just
like the one I have here?
Investigate how this pattern of squares continues. You could
measure lengths, areas and angles.
These pictures were made by starting with a square, finding the
half-way point on each side and joining those points up. You could
investigate your own starting shape.
Read about David Hilbert who proved that any polygon could be cut up into a certain number of pieces that could be put back together to form any other polygon of equal area.
If I use 12 green tiles to represent my lawn, how many different
ways could I arrange them? How many border tiles would I need each
How would you move the bands on the pegboard to alter these shapes?
Can you rank these sets of quantities in order, from smallest to largest? Can you provide convincing evidence for your rankings?
How many ways can you find of tiling the square patio, using square
tiles of different sizes?
This practical challenge invites you to investigate the different
squares you can make on a square geoboard or pegboard.
Grandpa was measuring a rug using yards, feet and inches. Can you
help William to work out its area?
Look at the mathematics that is all around us - this circular
window is a wonderful example.
This article for teachers gives some food for thought when teaching
ideas about area.
I cut this square into two different shapes. What can you say about
the relationship between them?
What do these two triangles have in common? How are they related?
Nine squares with side lengths 1, 4, 7, 8, 9, 10, 14, 15, and 18 cm can be fitted together to form a rectangle. What are the dimensions of the rectangle?
What is the smallest number of tiles needed to tile this patio? Can
you investigate patios of different sizes?
My measurements have got all jumbled up! Swap them around and see
if you can find a combination where every measurement is valid.
A simple visual exploration into halving and doubling.
Use the information on these cards to draw the shape that is being described.
Investigate all the different squares you can make on this 5 by 5
grid by making your starting side go from the bottom left hand
point. Can you find out the areas of all these squares?
You have pitched your tent (the red triangle) on an island. Can you
move it to the position shown by the purple triangle making sure
you obey the rules?
Have a good look at these images. Can you describe what is happening? There are plenty more images like this on NRICH's Exploring Squares CD.
Can you help the children find the two triangles which have the
lengths of two sides numerically equal to their areas?
What shape has Harry drawn on this clock face? Can you find its
area? What is the largest number of square tiles that could cover
Arrange your fences to make the largest rectangular space you can. Try with four fences, then five, then six etc.
It's easy to work out the areas of most squares that we meet, but
what if they were tilted?
What happens to the area of a square if you double the length of
the sides? Try the same thing with rectangles, diamonds and other
shapes. How do the four smaller ones fit into the larger one?
What is the total area of the four outside triangles which are
outlined in red in this arrangement of squares inside each other?
Prove that a triangle with sides of length 5, 5 and 6 has the same area as a triangle with sides of length 5, 5 and 8. Find other pairs of non-congruent isosceles triangles which have equal areas.
Can you draw a square in which the perimeter is numerically equal
to the area?
Here are many ideas for you to investigate - all linked with the
A circle with the radius of 2.2 centimetres is drawn touching the sides of a square. What area of the square is NOT covered by the circle?
Use the interactivity to find all the different right-angled
triangles you can make by just moving one corner of the starting
Place four pebbles on the sand in the form of a square. Keep adding
as few pebbles as necessary to double the area. How many extra
pebbles are added each time?
Can you work out the area of the inner square and give an
explanation of how you did it?
It is possible to dissect any square into smaller squares. What is
the minimum number of squares a 13 by 13 square can be dissected
A follow-up activity to Tiles in the Garden.
In this game for two players, you throw two dice and find the product. How many shapes can you draw on the grid which have that area or perimeter?
My local DIY shop calculates the price of its windows according to the area of glass and the length of frame used. Can you work out how they arrived at these prices?
A thoughtful shepherd used bales of straw to protect the area
around his lambs. Explore how you can arrange the bales.
Investigate the area of 'slices' cut off this cube of cheese. What
would happen if you had different-sized block of cheese to start
Cut differently-sized square corners from a square piece of paper
to make boxes without lids. Do they all have the same volume?
These rectangles have been torn. How many squares did each one have
inside it before it was ripped?
Which is a better fit, a square peg in a round hole or a round peg
in a square hole?
What is the largest number of circles we can fit into the frame
without them overlapping? How do you know? What will happen if you
try the other shapes?
An investigation that gives you the opportunity to make and justify
How many tiles do we need to tile these patios?
What can you say about these shapes? This problem challenges you to
create shapes with different areas and perimeters.
Explore one of these five pictures.
An activity for high-attaining learners which involves making a new cylinder from a cardboard tube.