Can you rank these sets of quantities in order, from smallest to largest? Can you provide convincing evidence for your rankings?

My measurements have got all jumbled up! Swap them around and see if you can find a combination where every measurement is valid.

Measure problems at primary level that require careful consideration.

Measure problems at primary level that may require determination.

Measure problems for primary learners to work on with others.

Measure problems for inquiring primary learners.

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.

I cut this square into two different shapes. What can you say about the relationship between them?

Investigate how this pattern of squares continues. You could measure lengths, areas and angles.

How many centimetres of rope will I need to make another mat just like the one I have here?

What do these two triangles have in common? How are they related?

Can you find rectangles where the value of the area is the same as the value of the perimeter?

Identical squares of side one unit contain some circles shaded blue. In which of the four examples is the shaded area greatest?

Look at the mathematics that is all around us - this circular window is a wonderful example.

I'm thinking of a rectangle with an area of 24. What could its perimeter be?

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?

What is the smallest number of tiles needed to tile this patio? Can you investigate patios of different sizes?

This article for teachers gives some food for thought when teaching ideas about area.

Bluey-green, white and transparent squares with a few odd bits of shapes around the perimeter. But, how many squares are there of each type in the complete circle? Study the picture and make. . . .

Cut differently-sized square corners from a square piece of paper to make boxes without lids. Do they all have the same volume?

Explore this interactivity and see if you can work out what it does. Could you use it to estimate the area of a shape?

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?

Determine the total shaded area of the 'kissing triangles'.

Grandpa was measuring a rug using yards, feet and inches. Can you help William to work out its area?

An activity for high-attaining learners which involves making a new cylinder from a cardboard tube.

It's easy to work out the areas of most squares that we meet, but what if they were tilted?

If you have only 40 metres of fencing available, what is the maximum area of land you can fence off?

An investigation that gives you the opportunity to make and justify predictions.

Use the interactivity to find all the different right-angled triangles you can make by just moving one corner of the starting triangle.

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?

A task which depends on members of the group noticing the needs of others and responding.

Use the information on these cards to draw the shape that is being described.

A simple visual exploration into halving and doubling.

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?

Are these statements always true, sometimes true or never true?

What is the largest 'ribbon square' you can make? And the smallest? How many different squares can you make altogether?

These practical challenges are all about making a 'tray' and covering it with paper.

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?

What happens to the area and volume of 2D and 3D shapes when you enlarge them?

Follow the instructions and you can take a rectangle, cut it into 4 pieces, discard two small triangles, put together the remaining two pieces and end up with a rectangle the same size. Try it!

Imagine different shaped vessels being filled. Can you work out what the graphs of the water level should look like?

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?

What can you say about these shapes? This problem challenges you to create shapes with different areas and perimeters.

A thoughtful shepherd used bales of straw to protect the area around his lambs. Explore how you can arrange the bales.