How many triangles can you make on the 3 by 3 pegboard?
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?
Have a go at making a few of these shapes from paper in different sizes. What patterns can you create?
If you split the square into these two pieces, it is possible to fit the pieces together again to make a new shape. How many new shapes can you make?
We have a box of cubes, triangular prisms, cones, cuboids, cylinders and tetrahedrons. Which of the buildings would fall down if we tried to make them?
Can you work out what shape is made when this piece of paper is folded up using the crease pattern shown?
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?
Can you describe a piece of paper clearly enough for your partner to know which piece it is?
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?
Using a loop of string stretched around three of your fingers, what different triangles can you make? Draw them and sort them into groups.
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 the 5 cubes so that you need the smallest number of Brush Loads of paint to cover them? Try with other numbers of cubes as well.
How can you put five cereal packets together to make different shapes if you must put them face-to-face?
Can you make dice stairs using the rules stated? How do you know you have all the possible stairs?
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.
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?
In this town, houses are built with one room for each person. There are some families of seven people living in the town. In how many different ways can they build their houses?
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.
Try continuing these patterns made from triangles. Can you create your own repeating pattern?
How many models can you find which obey these rules?
This practical activity challenges you to create symmetrical designs by cutting a square into strips.
What is the greatest number of counters you can place on the grid below without four of them lying at the corners of a square?
This practical investigation invites you to make tessellating shapes in a similar way to the artist Escher.
This problem focuses on Dienes' Logiblocs. What is the same and what is different about these pairs of shapes? Can you describe the shapes in the picture?
Can you order pictures of the development of a frog from frogspawn and of a bean seed growing into a plant?
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?
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?
Can you make the most extraordinary, the most amazing, the most unusual patterns/designs from these triangles which are made in a special way?
Is there a best way to stack cans? What do different supermarkets do? How high can you safely stack the cans?
These practical challenges are all about making a 'tray' and covering it with paper.
Explore the triangles that can be made with seven sticks of the same length.
You'll need a collection of cups for this activity.
Are all the possible combinations of two shapes included in this set of 27 cards? How do you know?
Sara and Will were sorting some pictures of shapes on cards. "I'll collect the circles," said Sara. "I'll take the red ones," answered Will. Can you see any cards they would both want?
Investigate the smallest number of moves it takes to turn these mats upside-down if you can only turn exactly three at a time.
An activity making various patterns with 2 x 1 rectangular tiles.
Make a chair and table out of interlocking cubes, making sure that the chair fits under the table!
NRICH December 2006 advent calendar - a new tangram for each day in the run-up to Christmas.
You have a set of the digits from 0 – 9. Can you arrange these in the 5 boxes to make two-digit numbers as close to the targets as possible?
Use the three triangles to fill these outline shapes. Perhaps you can create some of your own shapes for a friend to fill?
Make your own double-sided magic square. But can you complete both sides once you've made the pieces?
Can you see which tile is the odd one out in this design? Using the basic tile, can you make a repeating pattern to decorate our wall?
The Man is much smaller than us. Can you use the picture of him next to a mug to estimate his height and how much tea he drinks?
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?
Ahmed is making rods using different numbers of cubes. Which rod is twice the length of his first rod?
Can you make the birds from the egg tangram?
We can cut a small triangle off the corner of a square and then fit the two pieces together. Can you work out how these shapes are made from the two pieces?
How many different cuboids can you make when you use four CDs or DVDs? How about using five, then six?
Have you noticed that triangles are used in manmade structures? Perhaps there is a good reason for this? 'Test a Triangle' and see how rigid triangles are.
Can you split each of the shapes below in half so that the two parts are exactly the same?