A geoboard is a device commonly used in elementary schools to aid in the teaching of basic geometric concepts. A simple geoboard can be made from a square piece of wood and 25 nails arranged in an evenly-spaced grid of 5 vertical lines and 5 horizontal lines. These nails represent the lattice points in the plane. Figures are made on the geoboard by stretching rubber bands from one nail to another until the desired shape is formed.