Polyominoes is the name given to shapes made by joining squares together.
The most famous are dominoes and Tetris, the puzzle game which uses four square blocks or tetrominoes.
When you join five squares together you get pentominoes of which there are 12 different arrangements named after letters of the alphabet. A variety of intriguing spatial ability problems and exciting investigations can be crafted using pentominoes.
A great place to start is to use them as jigsaw pieces to fill a rectangle with an area of 60 squares. Possible sizes are 3x20, 4x15, 5x12 and 6x10.
The 3x20 rectangle has just two solutions but the 6x10 rectangle has 2,339 solutions.
Pentominoes can also be used to examine the concepts of congruence, similarity, transformations, tessellations, volume, perimeter and area. For example, using squared paper, challenge children to find the greatest possible area which can be trapped by a pentomino perimeter.
How efficiently can they join them together along the full edge of the square and not just the corners? You could go on to investigate which pentominoes have line symmetry or which will fold to make an open box
John Dabell is a numeracy consultant and teacher trainer