Can you work out what shape is made when this piece of paper is folded up using the crease pattern shown?
Move four sticks so there are exactly four triangles.
What is the total area of the four outside triangles which are outlined in red in this arrangement of squares inside each other?
Exploring and predicting folding, cutting and punching holes and making spirals.
What shape is the overlap when you slide one of these shapes half way across another? Can you picture it in your head? Use the interactivity to check your visualisation.
A group activity using visualisation of squares and triangles.
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?
Eight children each had a cube made from modelling clay. They cut them into four pieces which were all exactly the same shape and size. Whose pieces are the same? Can you decide who made each set?
Use the three triangles to fill these outline shapes. Perhaps you can create some of your own shapes for a friend to fill?
Imagine a 3 by 3 by 3 cube. If you and a friend drill holes in some of the small cubes in the ways described, how many will have holes drilled through them?
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 shape is made when you fold using this crease pattern? Can you make a ring design?
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?
Have a go at making a few of these shapes from paper in different sizes. What patterns can you create?
Can you describe a piece of paper clearly enough for your partner to know which piece it is?
How many different triangles can you make on a circular pegboard that has nine pegs?
Can you split each of the shapes below in half so that the two parts are exactly the same?
Draw three straight lines to separate these shapes into four groups - each group must contain one of each shape.
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?
Have you ever tried tessellating capital letters? Have a look at these examples and then try some for yourself.
Cut four triangles from a square as shown in the picture. How many different shapes can you make by fitting the four triangles back together?
How many loops of string have been used to make these patterns?
How many different cuboids can you make when you use four CDs or DVDs? How about using five, then six?
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?
How can the same pieces of the tangram make this bowl before and after it was chipped? Use the interactivity to try and work out what is going on!
An extension of noughts and crosses in which the grid is enlarged and the length of the winning line can to altered to 3, 4 or 5.
A magician took a suit of thirteen cards and held them in his hand face down. Every card he revealed had the same value as the one he had just finished spelling. How did this work?
This second article in the series refers to research about levels of development of spatial thinking and the possible influence of instruction.
Can you cut a regular hexagon into two pieces to make a parallelogram? Try cutting it into three pieces to make a rhombus!
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 ...
Paint a stripe on a cardboard roll. Can you predict what will happen when it is rolled across a sheet of paper?
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 fit the tangram pieces into the outline of Little Fung at the table?
Can you fit the tangram pieces into the outline of Little Ming playing the board game?
How many DIFFERENT quadrilaterals can be made by joining the dots on the 8-point circle?
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?
What can you see? What do you notice? What questions can you ask?
Can you fit the tangram pieces into the outlines of these clocks?
Can you fit the tangram pieces into the outlines of the chairs?
Can you fit the tangram pieces into the outline of this shape. How would you describe it?
Can you fit the tangram pieces into the outlines of the lobster, yacht and cyclist?
Can you fit the tangram pieces into the outline of the child walking home from school?
Find your way through the grid starting at 2 and following these operations. What number do you end on?
Investigate how the four L-shapes fit together to make an enlarged L-shape. You could explore this idea with other shapes too.
Can you fit the tangram pieces into the outline of Granma T?
If you can post the triangle with either the blue or yellow colour face up, how many ways can it be posted altogether?
Can you fit the tangram pieces into the outline of these convex shapes?
These points all mark the vertices (corners) of ten hidden squares. Can you find the 10 hidden squares?
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?