Pattern Blocks are a collection of six geometric shapes in six colors. Each set contains 250 pieces: 50 green triangles, 25 orange squares, 50 blue parallelograms, 50 tan rhombuses, 50 red trapexoids and 25 yellow hexagons.The blocks are designed so that their sides are all the same length with the exception that the trapexoid has one side twice as long. This set helps students explore congruence,similarity,syemmetry, area, perimeter, patterns, functions, fractions and grafting.