Working systematically

problem
Oranges and lemons, say the bells of St Clement's

Age

11 to 14

Challenge level

Bellringers have a special way to write down the patterns they ring. Learn about these patterns and draw some of your own.
problem
Sticks and triangles

Age

7 to 11

Challenge level

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?
problem
Coordinate challenge

Age

7 to 11

Challenge level

Use the clues about the symmetrical properties of these letters to place them on the grid.
problem
So many sums

Age

11 to 14

Challenge level

In this addition each letter stands for a different digit, with S standing for 3. What is the value of YxO?
problem
Intersection sums Sudoku

Age

7 to 16

Challenge level

A Sudoku with clues given as sums of entries.
problem
Flag-tastic

Age

11 to 14

Challenge level

How many different flags can you make?
problem
Fly away

Age

11 to 14

Challenge level

Can you work out the values of the digits in this addition sum?
problem
Making 11p

Age

11 to 14

Challenge level

How many ways are there to make 11p using 1p, 2p and 5p coins?
problem
Four-triangle arrangements

Age

5 to 7

Challenge level

How many different shapes can you make by putting four right- angled isosceles triangles together?
problem
Diagonal sums Sudoku

Age

7 to 16

Challenge level

Solve this Sudoku puzzle whose clues are in the form of sums of the numbers which should appear in diagonal opposite cells.