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 three triangles to fill these outline shapes. Perhaps you can create some of your own shapes for a friend to fill?
Can you visualise what shape this piece of paper will make when it is folded?
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?
What is the total area of the four outside triangles which are outlined in red in this arrangement of squares inside each other?
This practical problem challenges you to make quadrilaterals with a loop of string. You'll need some friends to help!
Paint a stripe on a cardboard roll. Can you predict what will happen when it is rolled across a sheet of paper?
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?
For this task, you'll need an A4 sheet and two A5 transparent sheets. Decide on a way of arranging the A5 sheets on top of the A4 sheet and explore ...
Can you work out what shape is made when this piece of paper is folded up using the crease pattern shown?
Choose a box and work out the smallest rectangle of paper needed to wrap it so that it is completely covered.
Have a go at making a few of these shapes from paper in different sizes. What patterns can you create?
Make a flower design using the same shape made out of different sizes of paper.
A group activity using visualisation of squares and triangles.
Can you work out what shape is made by folding in this way? Why not create some patterns using this shape but in different sizes?
What shape is made when you fold using this crease pattern? Can you make a ring design?
This problem invites you to build 3D shapes using two different triangles. Can you make the shapes from the pictures?
What is the greatest number of squares you can make by overlapping three squares?
Can you cut up a square in the way shown and make the pieces into a triangle?
Move four sticks so there are exactly four triangles.
Can you cut a regular hexagon into two pieces to make a parallelogram? Try cutting it into three pieces to make a rhombus!
You have been given three shapes made out of sponge: a sphere, a cylinder and a cone. Your challenge is to find out how to cut them to make different shapes for printing.
Make a cube out of straws and have a go at this practical challenge.
Looking at the picture of this Jomista Mat, can you decribe what you see? Why not try and make one yourself?
Use the lines on this figure to show how the square can be divided into 2 halves, 3 thirds, 6 sixths and 9 ninths.
Exploring and predicting folding, cutting and punching holes and making spirals.
Can you split each of the shapes below in half so that the two parts are exactly the same?
What are the next three numbers in this sequence? Can you explain why are they called pyramid numbers?
Have you ever tried tessellating capital letters? Have a look at these examples and then try some for yourself.
Have a look at what happens when you pull a reef knot and a granny knot tight. Which do you think is best for securing things together? Why?
Can you describe a piece of paper clearly enough for your partner to know which piece it is?
Can you fit the tangram pieces into the outline of Granma T?
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?
Can you fit the tangram pieces into the outlines of the convex shapes?
Can you fit the tangram pieces into the outline of the clock?
Can you fit the tangram pieces into the outline of the playing piece?
If you can post the triangle with either the blue or yellow colour face up, how many ways can it be posted altogether?
This article looks at levels of geometric thinking and the types of activities required to develop this thinking.
A hundred square has been printed on both sides of a piece of paper. What is on the back of 100? 58? 23? 19?
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?
Can you fit the tangram pieces into the outlines of the rabbits?
Here are shadows of some 3D shapes. What shapes could have made them?
Imagine a 3 by 3 by 3 cube made of 9 small cubes. Each face of the large cube is painted a different colour. How many small cubes will have two painted faces? Where are they?
Can you fit the tangram pieces into the outlines of Mah Ling and Chi Wing?
Reasoning about the number of matches needed to build squares that share their sides.
Can you fit the tangram pieces into the silhouette of the junk?
Can you fit the tangram pieces into the outline of the plaque design?
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?
Where can you put the mirror across the square so that you can still "see" the whole square? How many different positions are possible?