problem Can you Make 100? Age 11 to 14 Challenge level How many ways can you find to put in operation signs (+, −, ×, ÷) to make 100?
problem Charlie's delightful machine Age 11 to 16 Challenge level Here is a machine with four coloured lights. Can you develop a strategy to work out the rules controlling each light?
problem A little light thinking Age 14 to 16 Challenge level Here is a machine with four coloured lights. Can you make two lights switch on at once? Three lights? All four lights?
problem Partly Painted Cube Age 14 to 16 Challenge level Jo made a cube from some smaller cubes, painted some of the faces of the large cube, and then took it apart again. 45 small cubes had no paint on them at all. How many small cubes did Jo use?
problem Tower of Hanoi Age 11 to 14 Challenge level The Tower of Hanoi is an ancient mathematical challenge. Working on the building blocks may help you to explain the patterns you notice.
problem Elevenses Age 11 to 14 Challenge level How many pairs of numbers can you find that add up to a multiple of 11? Do you notice anything interesting about your results?
problem m, m and m Age 11 to 14 Challenge level If you are given the mean, median and mode of five positive whole numbers, can you find the numbers?
problem Find the Difference Age 5 to 7 Challenge level Place the numbers 1 to 6 in the circles so that each number is the difference between the two numbers just below it.
problem Data matching Age 14 to 18 Challenge level Use your skill and judgement to match the sets of random data.
problem Inside Triangles Age 5 to 7 Challenge level How many different triangles can you draw on the dotty grid which each have one dot in the middle?