Filter by: Content type: ALL Problems Articles Games Stage: All Stage 1&2 Stage 2&3 Stage 3&4 Stage 4&5 Challenge level:
What do these two triangles have in common? How are they related?
Can you help the children find the two triangles which have the lengths of two sides numerically equal to their areas?
My measurements have got all jumbled up! Swap them around and see if you can find a combination where every measurement is valid.
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 practical challenge invites you to investigate the different squares you can make on a square geoboard or pegboard.
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.
This article for teachers gives some food for thought when teaching ideas about area.
Can you draw a square in which the perimeter is numerically equal to the area?
How many centimetres of rope will I need to make another mat just like the one I have here?
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?
Investigate how this pattern of squares continues. You could measure lengths, areas and angles.
How many ways can you find of tiling the square patio, using square tiles of different sizes?
Arrange your fences to make the largest rectangular space you can. Try with four fences, then five, then six etc.
These rectangles have been torn. How many squares did each one have inside it before it was ripped?
Use the interactivity to find all the different right-angled triangles you can make by just moving one corner of the starting triangle.
What is the smallest number of tiles needed to tile this patio? Can you investigate patios of different sizes?
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?
Can you rank these sets of quantities in order, from smallest to largest? Can you provide convincing evidence for your rankings?
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.
Cut differently-sized square corners from a square piece of paper to make boxes without lids. Do they all have the same volume?
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?
Choose a box and work out the smallest rectangle of paper needed to wrap it so that it is completely covered.
A simple visual exploration into halving and doubling.
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.
Can you maximise the area available to a grazing goat?
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 this area?
What is the total area of the four outside triangles which are outlined in red in this arrangement of squares inside each other?
If you have only 40 metres of fencing available, what is the maximum area of land you can fence off?
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 into?
What can you say about these shapes? This problem challenges you to create shapes with different areas and perimeters.
I cut this square into two different shapes. What can you say about the relationship between them?
A thoughtful shepherd used bales of straw to protect the area around his lambs. Explore how you can arrange the bales.
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?
Seven small rectangular pictures have one inch wide frames. The frames are removed and the pictures are fitted together like a jigsaw to make a rectangle of length 12 inches. Find the dimensions of. . . .
Draw some isosceles triangles with an area of $9$cm$^2$ and a vertex at (20,20). If all the vertices must have whole number coordinates, how many is it possible to draw?
How would you move the bands on the pegboard to alter these shapes?
An investigation that gives you the opportunity to make and justify predictions.
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?
Points P, Q, R and S each divide the sides AB, BC, CD and DA respectively in the ratio of 2 : 1. Join the points. What is the area of the parallelogram PQRS in relation to the original rectangle?
How many tiles do we need to tile these patios?
Explore one of these five pictures.
Explore this interactivity and see if you can work out what it does. Could you use it to estimate the area of a shape?
It's easy to work out the areas of most squares that we meet, but what if they were tilted?
A follow-up activity to Tiles in the Garden.
The area of a square inscribed in a circle with a unit radius is, satisfyingly, 2. What is the area of a regular hexagon inscribed in a circle with a unit radius?
Can you find the area of a parallelogram defined by two vectors?
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 time?
This rectangle is cut into five pieces which fit exactly into a triangular outline and also into a square outline where the triangle, the rectangle and the square have equal areas.
Do you know how to find the area of a triangle? You can count the squares. What happens if we turn the triangle on end? Press the button and see. Try counting the number of units in the triangle now. . . .