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.
What shapes can you make by folding an A4 piece of paper?
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 these kite and dart templates, you could try to recreate part
of Penrose's famous tessellation or design one yourself.
Follow these instructions to make a three-piece and/or seven-piece
Make a mobius band and investigate its properties.
How can you make an angle of 60 degrees by folding a sheet of paper
Make a clinometer and use it to help you estimate the heights of
Make a ball from triangles!
Make an equilateral triangle by folding paper and use it to make
patterns of your own.
Make a cube with three strips of paper. Colour three faces or use
the numbers 1 to 6 to make a die.
Surprise your friends with this magic square trick.
Can you cut a regular hexagon into two pieces to make a
parallelogram? Try cutting it into three pieces to make a rhombus!
Have a go at drawing these stars which use six points drawn around
a circle. Perhaps you can create your own designs?
How can you make a curve from straight strips of paper?
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.
These practical challenges are all about making a 'tray' and covering it with paper.
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?
What do these two triangles have in common? How are they related?
How many triangles can you make on the 3 by 3 pegboard?
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?
Ideas for practical ways of representing data such as Venn and
How many differently shaped rectangles can you build using these
equilateral and isosceles triangles? Can you make a square?
Did you know mazes tell stories? Find out more about mazes and make
one of your own.
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?
Follow the diagrams to make this patchwork piece, based on an
octagon in a square.
How many models can you find which obey these rules?
If you'd like to know more about Primary Maths Masterclasses, this
is the package to read! Find out about current groups in your
region or how to set up your own.
Can you order pictures of the development of a frog from frogspawn
and of a bean seed growing into a plant?
This activity investigates how you might make squares and pentominoes from Polydron.
Kaia is sure that her father has worn a particular tie twice a week
in at least five of the last ten weeks, but her father disagrees.
Who do you think is right?
Can you create more models that follow these rules?
You could use just coloured pencils and paper to create this
design, but it will be more eye-catching if you can get hold of
hammer, nails and string.
These are pictures of the sea defences at New Brighton. Can you
work out what a basic shape might be in both images of the sea wall
and work out a way they might fit together?
NRICH December 2006 advent calendar - a new tangram for each day in
the run-up to Christmas.
Can you make the most extraordinary, the most amazing, the most
unusual patterns/designs from these triangles which are made in a
This practical problem challenges you to create shapes and patterns
with two different types of triangle. You could even try
I start with a red, a green and a blue marble. I can trade any of my marbles for two others, one of each colour. Can I end up with five more blue marbles than red after a number of such trades?
Can you fit the tangram pieces into the outline of Little Ming playing the board game?
Can you fit the tangram pieces into the outline of this telephone?
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
Can you fit the tangram pieces into the outline of this brazier for roasting chestnuts?
Can you fit the tangram pieces into the outlines of these people?
Can you describe what happens in this film?
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?
Can you recreate this Indian screen pattern? Can you make up
similar patterns of your own?
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 fit the tangram pieces into the outline of Wai Ping, Wah Ming and Chi Wing?