What is the smallest cuboid that you can put in this box so that you cannot fit another that's the same into it?

The challenge here is to find as many routes as you can for a fence to go so that this town is divided up into two halves, each with 8 blocks.

When newspaper pages get separated at home we have to try to sort them out and get things in the correct order. How many ways can we arrange these pages so that the numbering may be different?

How can you put five cereal packets together to make different shapes if you must put them face-to-face?

Ana and Ross looked in a trunk in the attic. They found old cloaks and gowns, hats and masks. How many possible costumes could they make?

Let's say you can only use two different lengths - 2 units and 4 units. Using just these 2 lengths as the edges how many different cuboids can you make?

If we had 16 light bars which digital numbers could we make? How will you know you've found them all?

How many models can you find which obey these rules?

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

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

You cannot choose a selection of ice cream flavours that includes totally what someone has already chosen. Have a go and find all the different ways in which seven children can have ice cream.

If you have three circular objects, you could arrange them so that they are separate, touching, overlapping or inside each other. Can you investigate all the different possibilities?

If you had 36 cubes, what different cuboids could you make?

Can you draw a square in which the perimeter is numerically equal to the area?

This task, written for the National Young Mathematicians' Award 2016, involves open-topped boxes made with interlocking cubes. Explore the number of units of paint that are needed to cover the boxes. . . .

How many different triangles can you make on a circular pegboard that has nine pegs?

How many different ways can you find of fitting five hexagons together? How will you know you have found all the ways?

Are all the possible combinations of two shapes included in this set of 27 cards? How do you know?

The letters of the word ABACUS have been arranged in the shape of a triangle. How many different ways can you find to read the word ABACUS from this triangular pattern?

This 100 square jigsaw is written in code. It starts with 1 and ends with 100. Can you build it up?

Kate has eight multilink cubes. She has two red ones, two yellow, two green and two blue. She wants to fit them together to make a cube so that each colour shows on each face just once.

Find a cuboid (with edges of integer values) that has a surface area of exactly 100 square units. Is there more than one? Can you find them all?

Can you put the numbers 1 to 8 into the circles so that the four calculations are correct?

In how many ways can you fit two of these yellow triangles together? Can you predict the number of ways two blue triangles can be fitted together?

This challenge extends the Plants investigation so now four or more children are involved.

Place the numbers 1 to 10 in the circles so that each number is the difference between the two numbers just below it.

Can you order pictures of the development of a frog from frogspawn and of a bean seed growing into a plant?

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

Arrange 9 red cubes, 9 blue cubes and 9 yellow cubes into a large 3 by 3 cube. No row or column of cubes must contain two cubes of the same colour.

Make your own double-sided magic square. But can you complete both sides once you've made the pieces?

10 space travellers are waiting to board their spaceships. There are two rows of seats in the waiting room. Using the rules, where are they all sitting? Can you find all the possible ways?

Put 10 counters in a row. Find a way to arrange the counters into five pairs, evenly spaced in a row, in just 5 moves, using the rules.

What is the best way to shunt these carriages so that each train can continue its journey?

Can you shunt the trucks so that the Cattle truck and the Sheep truck change places and the Engine is back on the main line?

Swap the stars with the moons, using only knights' moves (as on a chess board). What is the smallest number of moves possible?

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

Place eight queens on an chessboard (an 8 by 8 grid) so that none can capture any of the others.

Place eight dots on this diagram, so that there are only two dots on each straight line and only two dots on each circle.

How many DIFFERENT quadrilaterals can be made by joining the dots on the 8-point circle?

Take 5 cubes of one colour and 2 of another colour. How many different ways can you join them if the 5 must touch the table and the 2 must not touch the table?

Investigate the different ways you could split up these rooms so that you have double the number.

Take a rectangle of paper and fold it in half, and half again, to make four smaller rectangles. How many different ways can you fold it up?

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

You have 4 red and 5 blue counters. How many ways can they be placed on a 3 by 3 grid so that all the rows columns and diagonals have an even number of red counters?

Is it possible to place 2 counters on the 3 by 3 grid so that there is an even number of counters in every row and every column? How about if you have 3 counters or 4 counters or....?

This challenging activity involves finding different ways to distribute fifteen items among four sets, when the sets must include three, four, five and six items.

This practical challenge invites you to investigate the different squares you can make on a square geoboard or pegboard.

Building up a simple Celtic knot. Try the interactivity or download the cards or have a go on squared paper.

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

In how many ways can you stack these rods, following the rules?