I cut this square into two different shapes. What can you say about the relationship between them?
How can you change the area of a shape but keep its perimeter the same? How can you change the perimeter but keep the area the same?
What fractions of the largest circle are the two shaded regions?
Investigate the different ways of cutting a perfectly circular pie into equal pieces using exactly 3 cuts. The cuts have to be along chords of the circle (which might be diameters).
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?
Grandpa was measuring a rug using yards, feet and inches. Can you help William to work out its area?
Measure problems at primary level that may require determination.
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.
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?
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 number 2000.
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.
How would you move the bands on the pegboard to alter these shapes?
Polygons drawn on square dotty paper have dots on their perimeter (p) and often internal (i) ones as well. Find a relationship between p, i and the area of the polygons.
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.
Measure problems at primary level that require careful consideration.
Measure problems for inquiring primary learners.
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?
Use the information on these cards to draw the shape that is being described.
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?
What is the largest 'ribbon square' you can make? And the smallest? How many different squares can you make altogether?
Are these statements always true, sometimes true or never true?
A simple visual exploration into halving and doubling.
I'm thinking of a rectangle with an area of 24. What could its perimeter be?
Look at the mathematics that is all around us - this circular window is a wonderful example.
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?
What happens to the area and volume of 2D and 3D shapes when you enlarge them?
What can you say about these shapes? This problem challenges you to create shapes with different areas and perimeters.
How many tiles do we need to tile these patios?
Measure problems for primary learners to work on with others.
How many centimetres of rope will I need to make another mat just like the one I have here?
Which is a better fit, a square peg in a round hole or a round peg in a square hole?
Can you find rectangles where the value of the area is the same as the value of the perimeter?
How have "Warmsnug" arrived at the prices shown on their windows? Which window has been given an incorrect price?
What are the areas of these triangles? What do you notice? Can you generalise to other "families" of triangles?
Determine the total shaded area of the 'kissing triangles'.
At the corner of the cube circular arcs are drawn and the area enclosed shaded. What fraction of the surface area of the cube is shaded? Try working out the answer without recourse to pencil and. . . .
Investigate the area of 'slices' cut off this cube of cheese. What would happen if you had different-sized block of cheese to start with?
A thoughtful shepherd used bales of straw to protect the area around his lambs. Explore how you can arrange the bales.
Imagine different shaped vessels being filled. Can you work out what the graphs of the water level should look like?
A task which depends on members of the group noticing the needs of others and responding.
Use the interactivity to find all the different right-angled triangles you can make by just moving one corner of the starting triangle.
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?
Explore this interactivity and see if you can work out what it does. Could you use it to estimate the area of a shape?
Semicircles are drawn on the sides of a rectangle ABCD. A circle passing through points ABCD carves out four crescent-shaped regions. Prove that the sum of the areas of the four crescents is equal to. . . .
These rectangles have been torn. How many squares did each one have inside it before it was ripped?
Can you work out the area of the inner square and give an explanation of how you did it?
You have a 12 by 9 foot carpet with an 8 by 1 foot hole exactly in the middle. Cut the carpet into two pieces to make a 10 by 10 foot square carpet.
An investigation that gives you the opportunity to make and justify predictions.