Working systematically

Place eight queens on an chessboard (an 8 by 8 grid) so that none can capture any of the others.

Can you help the children find the two triangles which have the lengths of two sides numerically equal to their areas?

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

60 pieces and a challenge. What can you make and how many of the pieces can you use creating skeleton polyhedra?

This Sudoku, based on differences. Using the one clue number can you find the solution?

Rather than using the numbers 1-9, this sudoku uses the nine different letters used to make the words "Advent Calendar".

This Sudoku combines all four arithmetic operations.

What is the smallest number of ferry trips that Neda needs to take to visit all four islands and return to the mainland?

Alberta won't reveal her age. Can you work it out from these clues?

This practical challenge invites you to investigate the different squares you can make on a square geoboard or pegboard.