Two stones
This game is known as Pong hau k'i in China and Ou-moul-ko-no in Korea. Why not challenge a friend to play it with you?
A city of towers
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?
Skip counting
Butterfly flowers
Can you find two butterflies to go on each flower so that the numbers on each pair of butterflies adds to the number on their flower?
Nim-7
What shape and colour?
Can you fill in the empty boxes in the grid with the right shape and colour?
Share bears
Robot monsters
Sort the street
Sort the houses in my street into different groups. Can you do it in any other ways?
Number lines
Two-digit targets
You have a set of the digits from 0 to 9. Can you arrange these in the five boxes to make two-digit numbers as close to the targets as possible?
What is the time?
Incey wincey spider
Seeing squares
Players take it in turns to choose a dot on the grid. The winner is the first to have four dots that can be joined to form a square.
Four triangles puzzle
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?
Biscuit decorations
Whose face?
Teddy bear line-up
Missing middles
Making sticks
Domino join up
Four colours
Make 37
Four bags contain a large number of 1s, 3s, 5s and 7s. Can you pick any ten numbers from the bags so that their total is 37?
Teddy town
There are nine teddies in Teddy Town - three red, three blue and three yellow. There are also nine houses, three of each colour. Can you put them on the map of Teddy Town according to the rules?
Three block towers
Teddy town - part two
There are nine teddies in Teddy Town - three red, three blue and three yellow. There are also nine houses, three of each colour. Can you put them on the map of Teddy Town according to the rules?
Ladybird box
Teddy town - part three
There are sixteen teddies in Teddy Town - four red, four blue, four yellow and four green. There are also sixteen houses, four of each colour. Can you put them on the map of Teddy Town according to the rules?
Teddy town - part four
There are twenty five teddies in Teddy Town - five red, five blue, five yellow, five green and five purple. There are also twenty five houses, five of each colour. Can you put them on the map of Teddy Town according to the rules?
Teddy town - part five
There are thirty six teddies in Teddy Town - six red, six blue, six yellow, six green, six purple and six turquoise. There are also thirty six houses, six of each colour. Can you put them on the map of Teddy Town according to the rules?
Three by three
Mixed-up socks
Three way mix up
4 dom
The third dimension
Here are four cubes joined together. How many other arrangements of four cubes can you find? Can you draw them on dotty paper?