Sort the houses in my street into different groups. Can you do it in any other ways?
Explore the triangles that can be made with seven sticks of the same length.
Use the interactivity to investigate what kinds of triangles can be drawn on peg boards with different numbers of pegs.
Use your mouse to move the red and green parts of this disc. Can you make images which show the turnings described?
How many triangles can you make on the 3 by 3 pegboard?
This practical problem challenges you to create shapes and patterns with two different types of triangle. You could even try overlapping them.
Can you make the most extraordinary, the most amazing, the most unusual patterns/designs from these triangles which are made in a special way?
What do these two triangles have in common? How are they related?
Try continuing these patterns made from triangles. Can you create your own repeating pattern?
Using different numbers of sticks, how many different triangles are you able to make? Can you make any rules about the numbers of sticks that make the most triangles?
Investigate the number of paths you can take from one vertex to another in these 3D shapes. Is it possible to take an odd number and an even number of paths to the same vertex?
Can you create more models that follow these rules?
This challenge involves eight three-cube models made from interlocking cubes. Investigate different ways of putting the models together then compare your constructions.
These pictures show squares split into halves. Can you find other ways?
This practical investigation invites you to make tessellating shapes in a similar way to the artist Escher.
The ancient Egyptians were said to make right-angled triangles using a rope with twelve equal sections divided by knots. What other triangles could you make if you had a rope like this?
A group of children are discussing the height of a tall tree. How would you go about finding out its height?
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?
Arrange your fences to make the largest rectangular space you can. Try with four fences, then five, then six etc.
In this challenge, you will work in a group to investigate circular fences enclosing trees that are planted in square or triangular arrangements.
Can you find ways of joining cubes together so that 28 faces are visible?
Explore the different tunes you can make with these five gourds. What are the similarities and differences between the two tunes you are given?
Make new patterns from simple turning instructions. You can have a go using pencil and paper or with a floor robot.
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?
Is there a best way to stack cans? What do different supermarkets do? How high can you safely stack the cans?
We went to the cinema and decided to buy some bags of popcorn so we asked about the prices. Investigate how much popcorn each bag holds so find out which we might have bought.
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?
Use the interactivity to find all the different right-angled triangles you can make by just moving one corner of the starting triangle.
How many different cuboids can you make when you use four CDs or DVDs? How about using five, then six?
How many models can you find which obey these rules?
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?
How many different ways can you find of fitting five hexagons together? How will you know you have found all the ways?
What is the smallest cuboid that you can put in this box so that you cannot fit another that's the same into it?
How can you arrange these 10 matches in four piles so that when you move one match from three of the piles into the fourth, you end up with the same arrangement?
Vincent and Tara are making triangles with the class construction set. They have a pile of strips of different lengths. How many different triangles can they make?
An activity making various patterns with 2 x 1 rectangular tiles.
Have a go at this 3D extension to the Pebbles problem.
If we had 16 light bars which digital numbers could we make? How will you know you've found them all?
I like to walk along the cracks of the paving stones, but not the outside edge of the path itself. How many different routes can you find for me to take?
Polygonal numbers are those that are arranged in shapes as they enlarge. Explore the polygonal numbers drawn here.
Can you find out how the 6-triangle shape is transformed in these tessellations? Will the tessellations go on for ever? Why or why not?
This challenge extends the Plants investigation so now four or more children are involved.
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?
Suppose we allow ourselves to use three numbers less than 10 and multiply them together. How many different products can you find? How do you know you've got them all?
Lolla bought a balloon at the circus. She gave the clown six coins to pay for it. What could Lolla have paid for the balloon?
How many shapes can you build from three red and two green cubes? Can you use what you've found out to predict the number for four red and two green?
Investigate the different ways you could split up these rooms so that you have double the number.
This challenge involves calculating the number of candles needed on birthday cakes. It is an opportunity to explore numbers and discover new things.
How could you put eight beanbags in the hoops so that there are four in the blue hoop, five in the red and six in the yellow? Can you find all the ways of doing this?
There are to be 6 homes built on a new development site. They could be semi-detached, detached or terraced houses. How many different combinations of these can you find?